This is the second in a series of posts that will be reviewing and responding to the arguments of Dr. Feser's The Last Superstition. This was part 1. I haven't read many books of philosophy, and none aimed at popular audiences, so when I note that Dr. Feser starts out with a list of claims that he promises to demonstrate later, I have no idea if that is standard procedure or not. It does make the first chapter, Bad Religion, devoid of meaningful content with regard to establishing Dr. Feser's claims. However, one of the things I want to do is to in this post is list all these promises Dr. Feser makes in Chapter 1. After I review the last chapter, I will return to this list and we will see what has actually been proven.
Claims Dr. Feser says he will demonstrate
Secularism is inherently immoral and irrational, only a specific sort of religious view can be moral, rational, and sane
On intellectual grounds, atheism can not be true
Secularism can never spring from reason; its true grounding is from a willfulness and desire for it to be true
The basic metaphysical assumptions that make atheism possible are mistaken
Secular propaganda is the source of fideism
It is as impossible to say nature has no meaning or purpose as it is to square a circle (more on that below)
Secularism is parasitic on religion for all its important ideas, it is strictly a negation
What is characterized as a war between science and religion is really a war between competing metaphysical systems
The classical metaphysical picture is rationally unavoidable, and thus so is the traditional Western religious view derived from it
Given atheism and naturalism, there is no persuasive argument that allows you to trust in either reason or morality
Edit on 2009-NOV-17 to add: The abandonment of Aristotle's metaphysics has led to the abandonment of any rational or moral standards that can be used to justify moral positions, and is responsible for the curent civilizational crisis of the West.
Dr. Feser allows himself a full 241 pages in the next five chapters to accomplish all this. Of course, with so modest an undertaking, he leaves himself plenty of space to continue to denigrate atheism, secularism, the New Atheists (Dawkins, Dennett, Harris, and Hitchens), Hume, and many more in those chapters as well.
I do have a few other comments on some of Dr. Feser's remarks in chapter 1. While I still intend to avoid responding to the mere demagoguery that he indulges himself in, there are a few points that reveal interesting and noteworthy aspects of both him and his opinion of his audience.
There is nothing particularly noteworthy or striking about his claim that the less people know, they less they realize their ignorance. In fact, I read similar thoughts from a variety of science books and scientists growing up, typically along the lines of 'The more you know, the more you realize how little you know'.
I do not agree that attempts to account for phenomena such as the mind without referencing God is a religious discussion. You might as well say that attempts to account for lightning without referencing God is a religious discussion. Then again, perhaps Dr. Feser would say that. I would not be surprised at all to see him claim that any discussion of any natural phenomenon is inherently religious.
One of the common hallmarks of purveyors of woo is a sense of persecution that results from being treated equally. This comes out twice in Chapter 1, where first Dr. Feser complains that some philosophical positions distasteful to him are considered still worth discussion even when they can't be demonstrated, while the subject of religion is considered not to have made its case. Of course, the second standard is a far higher hurdle than the first, and certainly not to be awarded lightly. To imply that religion must be granted the second when other positions are granted the first, or else the supporters of the second are receiving unfair treatment, sounds very much like a persecution complex. Shortly after that, he complains that the distasteful propositions are referred to as making people think, whereas in this context religion is apparently not worthy of a moment's notice. He acknowledges that most people are raised religiously, but somehow misses the point that immersing people in thoughts they already find comfortable will be doing the opposite of making them think, it is much more likely to lull them to stupor. However, the concern seems to be for some sort of time equality, not purpose, because otherwise religious ideas are just not being treated fairly.
Dr. Feser pulls out the old saw about the desire to disbelieve in hellfire being a motivation for atheism. Oddly, I have met very few Christians who believed they, personally, were going to hell. I certainly never did, back in the day. He doesn't seem to understand the human tendency for exceptionalism, or to be deliberately ignoring it.
Dr. Feser declares that the notions of a selfish gene, or design via natural selection, can only be true and interesting if by these terms we attribute some superhuman, literal intelligence to the gene and the process. I'm not sure what to make of this. Obviously he knows the terms are metaphors that describe the complex interactions of various feedbacks mechanisms. He doesn't think that the study of feedback mechanisms is interesting, that the feedback mechanisms are not true, or that the use of metaphor makes the concept untrue or uninteresting?
Dr. Feser complains about 'Easter Bunny comparisons to God', which he disdains. This is all fine for him, but the authors upon whom he heaps this disdain are do not have the audience of his peers in mind; their books are for the general public, and often specifically the religious members thereof. The Easter Bunny example actually strikes right at the heart of what many of these people believe. If the religious group doesn't have their followers trained in the ideas of Aristotle, why should it be the job of Dennett, et. al., to train them? Later on, Dr. Feser says that this is an example of these authors not being willing to take on the real issues against the formidable opposition. With all the diminutions hurled against these authors, you would think he believe this is the appropriate level of opposition for them, but I suppose he thinks even more poorly of his fellow believers in this regard. At any rate, while I might not have the training of a Dennett, I am happy to accommodate Dr. Feser by engaging his ideas directly. Having read through Chapter 4 so far, I have not found any reason to see his presentation of reason, faith, and religion as having a superior metaphysical basis to your typical Sunday preacher.
Finally, Dr. Feser likes to make great use out of the metaphysical absurdity of square circles. He is unaware that all circles are indeed squares, under the taxicab metric (I'll devote a separate post to that). This is a problem with his metaphysical analysis that we’ll cover in more detail later. For now, let’s just say that like any other formal system, Aristotle’s metaphysics will turn out to be founded on arbitrarily chosen premises that are inherently improvable and not obviously better than a variety of alternatives as a description of reality.
Monday, October 19, 2009
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1,677 comments:
«Oldest ‹Older 201 – 400 of 1677 Newer› Newest»Jesus, Eric, does the bluster, bluff, hyperbole, and cocksure assertion without basis never end?
Eventually you get tired presenting it, or I get tired or reading you write it, for a short period of time.
I don't come to my understanding of how all "of the scientists involved" understand the notion of "causality" by reading mass media accounts by reporters, by resort to my own prejudices, etc.
Of course not. If you want to read how scientists use the language, you read what scientists write. You may have missed it, but there are a variety of scientists posting on the internet. Why you you bother to post such bluster? Trying to bluff me, engage in hyperbole, or just making some cocksure assertion?
I find such sources as the dictionary and/or lengthly theoretical discussions of the scientific meaning of "cause" much more reliable and accurate on such things.
I find either one is more likely to take you away from how scietists use the term than to take you closer to it.
There is clearly NO reason to discuss it further. The "majority of one" comment is wrong, but in any case it has become clear that you do not critically analyze many of these things,
You were criticizing me for bluster, bluffing, hyperbole, and cocksure assertions?
you merely inquire as to what you think the majority view is (at least if it favors the view you prefer to assert), and then adhere to it, with "common useage" as the only required criterion for acceptance and justification.
When it comes to what a word means, I would love to hear what you think is a better criterion than common usage. It can't be the dictionary, which is a compendium of common usage, not a protector from it. Lengthy theoretical discussion seem to be more likely to to specialized meanings, but that does not get you closer to how scientists use a word.
You "got" nothing. Cancer presumably has a "cause" is each instance it occurs (or, on your view, perhaps millions of causes in each instance it occurs).
It certainly does not have a single cause. It can't be runaway cell division, because the evidenced is that runaway cell division is more often caught and halted by the immune system. It can't be the cell being able to hide from the immune system, because most of those cells don't experience runaway cell division. Of course, if you allow for multiple causes, whether millions or fewer, than tobacco is among them. So, I can understand why this is a problem for you.
In some cases, that cause could be smokin, I dunno. In other cases, it might be chewing bubble gum, again, I dunno, and I guess I never will "know" unless and until they do a correlation study to see if there is "any" (whatsoever) positive correlation between the two (again, on your view)."
Why would they bother with a correlation study of tobacco and cancer when the mechanisms are so well known? Did you even read the link I offered? Do you think criticizing me for "bluster, bluff, hyperbole, and cocksure assertion" and then talking about the tobacco/cancer connection as if it is based principally on correlation makes you seem anything other than hypocritical?
I don't think you're even capable of seeing the difference.
Because if I saw the difference, I would automatically agree with you?
Even assuming that X "causes" Y one out a million times that Y occurs, and assuming that X only "causes" Y one out of a million times that X occurs, that simply is NOT a valid basis for the generalized, unqualified claim that "X causes Y" for anyone I know, or have ever heard of, except you.
I don't see how that is my fault. Outside of the occasional ivory-tower philosopher or person with an axe to grind, I don't ever recall anyone who insists "X causes Y" means that Y has to happen each and every time X does. I don't find "X always causes Y" to be redundant. You apparently do.
One Brow said: "Because the acceleration of the clocks and the relative speed differential is constant, the deviation from the speed of our clocks here on earth is constant."
What are you saying? You have already rejected a "constant deviation," I thought (you said there would be NO deviation, not a constant one).
I said, and you quoted, "Why would the relativistic conditions be continuously varying? The clocks are under a constant acceleration." While having no relativistic effects is consistent with that statement, so the the broader condition of unchanging, constant relatavistic effects. You seem to have confused "constant deviaiton" with "continuously varying" deviation.
Are you saying that if two objects are approaching each at .90C, their respective clocks will be the same (unless and until the relative speed differential varies by increasing to .89C or .91C)?
Each will see the other clock as being slower, if both are in inertial conditions.
I have no clue where you're getting this. Obviously your view is at odds with that of at least one trained physicists (Van Flandren) as well as with my understanding of every account of the phenomenon I have read.
Every physicist I have read on Van Flandern views him as a crank. His ideas led to no experimental results different from the current understanding, and seem to have been inferior in their understaning the effects of relativity on GPS.
Nothing I said disputes your quote on time dialation.
The specific reference here is to "uniform relative motion."
1) Uniform relative motion could be adjusted for by changing clock speed.
2) GPS satellites are under not in uniform raltive motion to the earth. Their velocity has a higher norm (they have greater speed), so they are accelerating faster.
What does the result of a "confirming" experiment tell you, and how much do the assumptions you bring to the process of interpreting "results" influence your conclusions?
The results extend the extrapolation of the inductve process to an additional circumstance, and often can begin to give you an approximate amount of responsibility one particular factor has on a result.
I bring this up again, because I don't recall you responding to my question about how and why you were so certain of the "nature of space" you recited. You seem to start with the assumption that that particular interpretation of "reality" is unquestionably true, and then proceed judge any other claim to "truth" as dependent upon corresponding to it.
The best evidence is that space is curved. Any statement about reality as revealed by sciencfe always have that caveat, even if I don't state it every time.
... and it is therefore not entirely coincidental that the effects exactly cancel."
They "exactly cancel"? Venus is about the size of Earth, with a slower rotation. If they exactly concel on Earth (which I find unlikely, since the effect on a mountaintop at the equater would be different from the effect at the bottom of an ocean trench), then they don't on Venus.
One Brow said: "Why would they bother with a correlation study of tobacco and cancer when the mechanisms are so well known? Did you even read the link I offered?"
You mean the one where one guy was speculating on possible mechanisms? If both the cause and the mechanisms are so "well known," I wonder why they haven't found a cure yet, eh?
It may be true that all fake clown noses are red, but even if it is, it does not follow that all red things are clown noses.
Likewise, even if all cancer is caused by smoking, it would not follow that all smoking causes cancer.
Even if some "scientists" somehow equate "cancer is caused by smoking" with "smoking causes cancer," that does not make the logic correct, nor does a misuse of language rewrite the rules of logic, set theory, or whatever you want to call it.
One Brow said: "which I find unlikely, since the effect on a mountaintop at the equater would be different from the effect at the bottom of an ocean trench)"
Why would you interpret a statement that clearly limits itself to sea level to be referring to mountaintops or trenches, I wonder?
One Brow said: "Each will see the other clock as being slower, if both are in inertial conditions."
Yeah, and what if one or the other is not "inertial?" Then both clocks will always be in complete agreement, that the idea?
Why didn't you just call Van Flandern a "crank" from the git-go, eh? You say he doesn't understand relativistic effects (you probably didn't even read the summary of his that I quoted, but let's leave that be, since once he is called a "crank" you are proven right).
Lemme just ax ya: What physicist who, in your opinion, is NOT a crank, agrees with you that clocks on orbiting satellites would not vary from those which are stationary on earth given SR assumptions? Can you name even one?
One Brow said: "The best evidence is that space is curved."
And this evidence is "best" because....
1. No other known assumptions could explain it?
2. It is the most "elegant" and mathematically appealing solution?
3. Both?
4. Neither?
Best I can tell, it is perhaps true, but kinda misleading, to say the designers of the GPS system "blew off Einstien." From what I understand, they avoided any problems with synchronizing satellite clocks with earth-bound clocks by choosing non-earth bounds "clocks" to adjust for time dilation, etc. As it currently functions, GPS does not provide any direct way of either confirming or disconfirming satellite-earth clock differentials. In that sense, they might have "blown off Einstein."
That said, Van Flandren does not contend that adjustments would not have to be made, he simply questions the reasons for that necessity. Lorentz, and many others, had shown that the assumptions of an ether, a preferred time frame, absolute time (with, therefore, a non-absolute speed of light) could also anticipate, and explain, the differences.
He summarizes the two views, and the possible reasons for deciding to prefer one over the other, as follows:
"We are, of course, free to question whether or not this [relativistic] mathematical theory retains a valid basis under the principles of causality. For those of us who answer "yes", LR [Lorentzian Relativity] is unnecessary, and inelegant because it depends on a preferred frame. For those of us who answer "no", LR is then the better descriptor of nature, requiring the sacrifice of symmetry (“covariance”) to retain causality."
http://www.metaresearch.org/cosmology/gps-relativity.asp
One Brow said: "Each will see the other clock as being slower, if both are in inertial conditions."
Although there is no contradiction involved in claiming that two observers will perceive a situation differently, it would be an inherent contradiction to claim that each clock IS (i.e., in "reality") running slower than the other. Relativity does not even purport to deal with what the "real" situation might be; it simply operationally defines what "is" in terms of what it is measured to be by a particular observer under particular conditions. Why would anyone choose a viewpoint which explicitly refuses to confront the issue of "objective reality" as the "best evidence" of what "objective reality" is, I wonder?
Simply positing an eternal realm of "forms" to solve the "problem of universals," as Plato did, might be the "most elegant solution." But elegance is not the "best evidence" of reality, is it?
Some people have a great deal of difficulty is seeing any difference in these two (radically different) statements, I guess:
1. Cancer is caused by smoking
2. Smoking causes cancer
They're equivalent statements, right? Wrong, no more than these two are:
1. All fake clown noses are red things
2. All red things are fake clown noses.
I repeat the point, because it seems very difficult for some to comprehend.
I said:
1. All fake clown noses are red things
2. All red things are fake clown noses.
Claim 1 could possibly be true, but even the most limited experience will tell you that claim 2 is false.
It seems to me, Eric, that having erroneously asserted the "truth" of claim 2, you then go to great lengths to defend it, come hell or high water, rather than re-assess your mistaken claim. You end up arguing to the effect that every "thing" is "red" in some degree, or some sense, in an attempt to defend it.
Edit: I should have said: You end up arguing to the effect that every "red thing" is in some degree, or some sense, a "fake clown nose" in an attempt to defend it.
One Brow said: "His ideas led to no experimental results different from the current understanding."
OK, so? What about his claim that the "current understanding" has led to no experimental results different from his ideas? Or does all this only work one way, with the rhetorical tactic of dismissing those who turn the question around as a "crank" being used to evade the question?
You say, if A + B = C, then B = C - A.
I say, right, and likewise, A = C - B.
You say: Wrong! There is no "likewise" about this. I'm talking only about what B is, not A.
Just in case you don't see the analogy here:
If I say a + b = c, and, furthermore, that c is always 10, then if a is 4, b must be 6. If a is 3 b must be 7; if a is .01, then b must be 9.99, and so on.
If, on the other hand, I say that a is always 5, then b and c must vary accordingly. If b is 12, then c must be 17, etc.
To quote Van Flandern again: "The single most important difference is that, in SR, nothing can propagate faster than c in forward time. In LR, electromagnetic-based forces and clocks would cease to operate at speeds of c or higher. But no problem in principle exists in attaining any speed whatever in forward time using forces such as gravity that retain their efficiency at high speeds."
The point, of course, is that as soon as you set one of the terms (a, b, or c) to be absolutely invariable, then it is the other 2 that must vary.
If you think that the "real world" dictates that c be invariable, then let me quote Einstein himself on the issue:
"Physical concepts are free creations of the human mind and are not, however it may seem, uniquely determined by the physical world." (1938, in a book with his associate Leopold Infeld, The Evolution of Physics.)
http://www.infinite-energy.com/iemagazine/issue38/einstein.html
According to this same source:
"Perhaps his [Einstein's] most serious expression of doubt came in a 1954 letter, the year before he died, to his friend Michel Besso: "I consider it quite possible that physics cannot be based on the field concept, i.e. on continuous structures. In that case, nothing remains of my entire castle in the air, gravitation theory included, and of the rest of modern physics...just a few years earlier (1948), in an introduction to a popularized book about relativity, Einstein was also circumspect about physics, in a more general sense: ". . .the growth of our factual knowledge, together with the striving for a unified theoretical conception comprising all empirical data, has led to the present situation which is characterized— notwithstanding all successes— by an uncertainty concerning the choice of basic theoretical concepts."
You may think I'm trying to argue about relativity here, but that's not my real point at all. Relativity is just a particular example of a subject where universal questions can be raised.
Van Flandern said: "...in SR, nothing can propagate faster than c in forward time.."
And why is this (or should this be) true?
"[Editor's note: Einstein's "second principle" is the postulate of the supposed constancy of light speed in vacuo to all observers.]"
http://www.infinite-energy.com/iemagazine/issue38/einstein.html
Aww, so it's a "postulate," eh? Kinda like Euclid's parallel line postulate, maybe? Haven't you already asserted that the postulates of formal theories in no way assure that the deduction made in reliance thereon will conform to the "real world?"
I asked you before, but you never answered that I could tell--does the description of a "scientific realist" seem to apply to your outlook, ya think?
One Brow said: "The clocks are under a constant acceleration.... You seem to have confused "constant deviaiton" with "continuously varying" deviation...GPS satellites'... velocity [have] a higher norm (they have greater speed), so they are accelerating faster."
Once again, I am beginning to suspect that we are using completely different definitions. The quote above, especially the last sentence, appears to imply that you believe greater speed means greater acceleration.
That is not my understanding at all. Speed and acceleration are completely independent concepts. Acceleration is essentially a CHANGE in speed (or direction if you want to refer to "velocity"), regardless of initial speed (or velocity). An object going 1 inch per year and one going 1,000,000 miles per hour are both travelling at uniform ("inertial" speeds) so long as the rate of speed is constant. Neither is accelerating at all. The relative motion between them remains uniform, and neither is "accelerating faster than the other."
Edit: Should have said: "An object going 1 inch per year and one going 1,000,000 miles per hour are both travelling at uniform ("inertial") speeds so long as the rate of speed is constant [ADD] and the direction of travel remains uniform."
For Newton, orbiting objects were accelerating in velocity because their "direction" of travel was constantly "changing." What was it changing from? The "straight line" posited in his second law of mechanics, that's what. It required a "force" for acceleration (which includes a change of direction when talking about velocity, as opposed to mere speed) to occur.
I do not believe that relativistic mechanics treat orbiting objects as accelerating at all in terms of directional change, therefore no "force" of gravity is required to keep them on the recurring path they maintain.
You mean the one where one guy was speculating on possible mechanisms? If both the cause and the mechanisms are so "well known," I wonder why they haven't found a cure yet, eh?
They cure lung cancers every day. However, since there is more than one type of lung cancer, a cure for one maight have no effect on another. Also, do you think it is easy to devise a method of killing human cells in cancer, or stopping cell reproduction in cancer, that doesn't kill other human cells or stop other, vital cell reporoduction?
Orac happened to talk about cancer today. He has directly said smoking causes cancer in prior posts. Of course, he's just a doctor and cancer researcher, so maybe he doesn't understand the vocabulary of scientists as well as you.
http://scienceblogs.com/insolence/2009/11/cancer_prevention_drugs_supplements_and.php
Kolata correctly points out that if we could eliminate smoking cancer deaths would decrease by about a third. ... Now lung cancer is the single largest cause of cancer deaths ... and it's all due to smoking... After all, I've already lost an aunt to smoking-induced lung cancer in 2008...
Likewise, even if all cancer is caused by smoking, it would not follow that all smoking causes cancer.
Of course not. Humans are too diverse to have identical results like that.
Even if some "scientists" somehow equate "cancer is caused by smoking" with "smoking causes cancer," that does not make the logic correct, nor does a misuse of language rewrite the rules of logic, set theory, or whatever you want to call it.
I have no intention of trying to get you to change how you use the word, nor your opinion of those who use it differently.
Why would you interpret a statement that clearly limits itself to sea level to be referring to mountaintops or trenches, I wonder?
What about Van Flandern's statements only refer to coordinating atomic clocks in orbit with those at sea level?
Yeah, and what if one or the other is not "inertial?" Then both clocks will always be in complete agreement, that the idea?
My understanding is that the clock in the framework under higher acceleration may see the other clock as moving in synchronization, or even faster. If you like, I could ask colton to join us and clarify, because I'm not sure.
Why didn't you just call Van Flandern a "crank" from the git-go, eh?
I have said it before.
You say he doesn't understand relativistic effects
I hope I was not that dogmatic. I probably questioned his understanding of the relativistic effects in a particular situation, and even then, said that it did not make sense to me.
Lemme just ax ya: What physicist who, in your opinion, is NOT a crank, agrees with you that clocks on orbiting satellites would not vary from those which are stationary on earth given SR assumptions?
When did that become my opinion? I said the variance would be constant, as opposed to fluctuating.
1. No other known assumptions could explain it?
2. It is the most "elegant" and mathematically appealing solution?
3. Both?
4. Neither?
A combination of the two. Van Flandern had to do a bit a jury-rigging to get his ideas to match the results of modern experiements, from what I recall reading, reminding me of when we said you could always add enough epicycles to force Ptolemic astronomy.
Although there is no contradiction involved in claiming that two observers will perceive a situation differently, it would be an inherent contradiction to claim that each clock IS (i.e., in "reality") running slower than the other.
Your statement assumesthere is a universal reference frame from which to judge the real speed of each clock.
Why would anyone choose a viewpoint which explicitly refuses to confront the issue of "objective reality" as the "best evidence" of what "objective reality" is, I wonder?
Both observers would be making objective measurements to confirm the other clock moved more slowly.
1. Cancer is caused by smoking
2. Smoking causes cancer
They're equivalent statements, right? Wrong, no more than these two are:
1. All fake clown noses are red things
2. All red things are fake clown noses.
For that to be true, the level of inclusion indicated by "to cause" must be the same as that indicated by "to be". Since other people don't subscribe to that definition, for them they are not the same thing.
As for the first two statements on cancer, I would say 1. less true than 2.
What about his claim that the "current understanding" has led to no experimental results different from his ideas? Or does all this only work one way, with the rhetorical tactic of dismissing those who turn the question around as a "crank" being used to evade the question?
My understanding is that he needed to jury-rig explanations to make his theory fit the data (which is why you will see him refer to the two-way speed of light and such things.
But no problem in principle exists in attaining any speed whatever in forward time using forces such as gravity that retain their efficiency at high speeds."
I would think that as one moving increases velocity, any source of gravitation will become more attracted to that mass that the original mass will besome attracted to the gravitaitonal source, due to the effects of mass increase on the original mass.
Aww, so it's a "postulate," eh? Kinda like Euclid's parallel line postulate, maybe? Haven't you already asserted that the postulates of formal theories in no way assure that the deduction made in reliance thereon will conform to the "real world?"
If SR was a formal system only, this would be true.
I asked you before, but you never answered that I could tell--does the description of a "scientific realist" seem to apply to your outlook, ya think?
I don't think so. It might depend on who is doing the applying.
The quote above, especially the last sentence, appears to imply that you believe greater speed means greater acceleration.
Satellites have an higher orbital speed that is greater than earth-bound objects, and the changes involved in a full rotation would be accompanied by greater acceleration. Your sentence is much too general.
I do not believe that relativistic mechanics treat orbiting objects as accelerating at all in terms of directional change, therefore no "force" of gravity is required to keep them on the recurring path they maintain.
http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html
They offer the same explanation I did: the rate of clock ticks were changed.
With regard to the presumed "crank" status of Van Flandern: Steve Carlip appears to be respected physicist at UC Davis who apparently extensively debated Van Flandern, over a course of years, about Van Flandern's contention that the speed of gravity must exceed the speed of light. Carlip always opposed Van Flandern's view in favor of a relativistic one. Van Flandern thanks Carlip for all the assistance as follows:
"Each of these challenges has forced a new and deeper investigation, without all of which the present paper could never have hoped to pass peer review. One relativist in particular, Steve Carlip of UC Davis, had the patience to stay with this issue over a span of several years, defending the GR interpretation to the fullest extent possible. Between us we have written enough prose, created enough analogies, pondered enough equations, and consulted enough references to fill a book."
http://www.metaresearch.org/cosmology/speed_of_gravity.asp
Carlip wrote a paper in response, but even he concedes that the issue is strictly theoretical one which has not been expermentially resolved at this point:
"what do experiments say about the speed of gravity? The answer, unfortunately, is that so far they say fairly little. In the absence of direct measurements of propagation speed, observations must be filtered through theory, and different theoretical assumptions lead to different deductions. In particular, while the observed absence of aberration is consistent with instantaneous propagation (with
an extra interaction somehow added on to explain the gravitational radiation reaction), it is also consistent with the speed-of-light propagation predicted by general relativity."
http://xxx.lanl.gov/PS_cache/gr-qc/pdf/9909/9909087v2.pdf
He certainly does not treat Van Flandern as a "crank," and acknowledges that his points have some merit. For example:
"It is certainly true, although perhaps not widely enough appreciated, that observations are incompatible with Newtonian gravity with a light-speed propagation delay added in...It is worth noting that the cancellation between aberration and velocity-dependent terms in general relativity is not quite exact...As Van Flandern has stressed, though, astronomical observations require a more complete cancellation: aberration terms of order v3/c3 must be eliminated as well."
The arguments are rather technical, but it appears that both sides concede that either theory is capable of explaining the experiments, but argue that their view has advantages over the others'.
That said, I have no doubt that, for some, anyone who does not endorse the prevailing scientific orthodoxy is suspected of, and perhaps readily accused of, being a "crank." This is the well-established, standard operating procedure for those with a "pc-enforcment" mentally, which mentality seems to pervade virtually every aspect of thought today, be it social, political, scientific, or whatever.
One Brow said: "They offer the same explanation I did: the rate of clock ticks were changed."
You may have suggested that in some subsequent post, but all of my posts on this have been directed toward your original response, which suggested that "constant accelation" (not clock recalibration) would dispense with any need for continuting adjustment. One Brow said: "Why would the relativistic conditions be continuously varying? The clocks are under a constant acceleration."
As I understand it, they did not change the rate of the "tock clicks," as you now suggest, in any event. The orbiting clocks continue to "tick" at their relativisticly slowed rates. The scientists simply defined what the clock would call a minute (or a second, or whatever).
The author you quoted never said the relativistic conditions would be continually varying to begin with. He said the relativistic conditions would require some type of correction on a continuous basis. Your reply, despite mis-stating the claim, suggested that no continuing corrections would be needed, because there would be no continuous error to "correct" for, since "constant acceleration" would dictate cause the clocks to read the same after launch.
In hindsight, who knows what you even meant, or what problem you even thought you were addressing, I just took it as directed toward the issue raised, but perhaps that was a mistake.
One Brow said: "Satellites have an higher orbital speed that is greater than earth-bound objects, and the changes involved in a full rotation would be accompanied by greater acceleration."
What "changes" would those be?
Would "greater acceleration" make the clocks run the same, or would they just increase the complications involved in figuring out the exact amount of the necessary corrections in order to synchronize clocks?
One Brow said: "If SR was a formal system only, this would be true."
What do you mean by "only?" What else is it? In what way does that "something else" make it different from euclidean geometry or newtonian mechanis?
One Brow said: "My understanding is that he needed to jury-rig explanations to make his theory fit the data"
Not sure what you mean by "jury-rig," but not sure why it would be relevant to my question in any event. "Jury-rigged" or not, has his (and many others, including Lorentz) explanation been experimentally disproved?
I have already stated my opinion on this topic: all theories are tinkered with to fit the facts. As Einstein himself (and innumerable others as well) has noted, the facts do NOT dictate the premises--they are the "free creation" of the mind, and no more. You apparently still seem to believe that the facts dictate that only a particular explanation can be advanced to account for them.
"Jury-rigging" the theory is not the same as "jury-rigging" (misrepresenting) the facts to conform to your theory, ya know?
Your first attempt to dismiss Van Flandern was to call him a crank.
Your next attempt was to say that his ideas had not disproved relativity (while ignoring that this may well be a two-way street, i.e., SR has not disproved his ideas, either).
Now you throw out a perjorative term like "jury-rigging" rather than respond to the question. All quite predictable. You don't analyze questions that might undermine your conclusions, you simply ignore them by insulting the questioner and/or by asserting that he is "guilty" of failing to do something your own view fails to do.
One Brow said: "What about Van Flandern's statements only refer to coordinating atomic clocks in orbit with those at sea level?"
I have no clue what you're even trying to suggest. The statement you "doubted" was: "Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth."
For what it's worth, Eric, I have seen it claimed that Einstien, Feynman, Dirac, and other illustrious physicists held to a "physcial force" view of gravity, and rejected a "geometrical" (curved space) one.
This is said to no longer be the "popular" view, and I suppose it is for that reason that you call it's alternative the "best evidence." The thoughts of such geniuses notwithstanding, the "true" view must always be the one perceived as being held by the majority of present-day scientists, whether they are particularly brilliant, or not, I spoze.
One Brow said: "For that to be true, the level of inclusion indicated by "to cause" must be the same as that indicated by "to be". Since other people don't subscribe to that definition, for them they are not the same thing."
Well, sure, you can define any word any way you want to prove your argument. If I want to "prove" that all red things are clown noses, I simply assert that: "Red things" means "clown noses," that's the way I define it."
My point is that while some may carelessly claim that "smoking causes cancer," I think they are really just making the logical mistake of thinking it is justified to say that on the basis of the conclusion that "cancer is caused by smoking."
When pushed, they will say that they believe that cancer is (or can be) caused by smoking, but that they are not really trying to insist that "smoking causes cancer" with the justification supposedly being that even the slightest increase in the "odds" of event x following event y "means" y causes x. The error is in their choice of language, not in the rejection of established definitions within the language.
I asked: Yeah, and what if one or the other is not "inertial?" Then both clocks will always be in complete agreement, that the idea?
One Brow said: My understanding is that the clock in the framework under higher acceleration may see the other clock as moving in synchronization, or even faster. If you like, I could ask colton to join us and clarify, because I'm not sure.
Well, I don't claim to be any kinda expert, and certainly don't know as much about physics as Colton. Even so, I think I have a passing understanding of the answer to this question that is generally given.
SR deals only with frames of reference which are moving at a uniform rate of speed in a "straight line" (for relativists, a "straight line" means the straightest line an object can follow given curved space, not a "straight line" as Newton and Euclid defined it). As such, it doesn't even address issues involving accelerated frames of references--it provides no answers, which is not to say that it doesn't imply them, but....
GR, among other things, introduces the "equivalence principle" which basically says that the effects of acceleration are indistinguishable from those of what newton called "gravity." The gravitional "force" which keeps us tied to earth (call it "one G") can be duplicated in part or whole, or even greatly multiplied, by acceleration is space. Any such acceleration is inherently limited, of course, because unlimited acceleration would eventually cause the object to exceed the speed of light. So there is no such thing as "constant acceleration."
But either way, accleration would simply be treated as an increase in the "gravitational" aspect of time dilation (as opposed to differences arising from differing speeds). It would not synchronize any two clocks, except in the extremely coincidental case where one effect exactly offset the other (as happens with 2 earth bound clock at sea level, irrespective of the longitude/latitude co-ordinate of either).
As was suggested in the post where this was originally brought up, the satelite must first be accelerated until it reaches the desired orbit height, at which point the original acceleration ceases, and it settles into uniform motion (unless and until other "forces" impinge on it to speed it up or slow it down). It is now in "free fall" at the same speed it had been accelerated to in order for it to reach the height it did. So this acceleration requires a "one-time" correction before it leaves earth. It does not recur. However the time-distortion effects of both relative speed and gravitation continue, and the absolute magnitude of the difference created will accumulate and compound with time, if left uncorrected. A difference of one second per hour will be 24 seconds per day, 8760 seconds per year, etc.
In one aspect, relativity and euclid both define a "straight line" in the same way, i.e., as the shortest distance between two points. The difference is that for Euclid the two points in question were, by definition, in the same two-dimensional plane. In relativity, the shortest distance is in 3 dimensions, and is qualified by the word "possible." A straight (Euclidean) line from New York to London would not be the shortest (time-wise) way to get there, because it would entail a 3,000 mile tunnel through the earth. As a practical matter, the "shortest" route is a curved line over the sea on the surface of the earth.
Although I find the subject of relativity inherently interesting, my main purpose for discussing it in this particular thread involves the instructiveness it can provide with respect to concepts of "truth," "reality," epistemology, etc. I think you and I have major differences in the way we perceive what relativity reveals about the nature of truth, reality, scientific theory, etc.
Steve Carlip ... extensively debated Van Flandern, over a course of years,
The presence of a debater is not a guarantee of the legitimacy of Van Flandern's position.
... he concedes that the issue is strictly theoretical one ...
He concedes one issue about the speed of gravity propagation not being experiementally verified. This does not validate Van Flandern's claims about matter exceeding c.
... anyone who does not endorse the prevailing scientific orthodoxy is suspected of, and perhaps readily accused of, being a "crank."
Do you think cranks exist? Is there something about Van Flandern's work that distinguishes it? String theory was also against the prevailing scientific orthodoxy? Why do you think string theory is treated differently from Van flandern's work? Do you think it's just arbitrary or politics?
As I understand it, they did not change the rate of the "tock clicks," as you now suggest, in any event. The orbiting clocks continue to "tick" at their relativisticly slowed rates. The scientists simply defined what the clock would call a minute (or a second, or whatever).
They changed the rate of a clock tick, prior to launching the satellites, so that while in orbit the ticks in the clocks would be of the same length as those on earth. Because the acceleration of the satellites is constant, there is no need to make continuing adjustments to the clocks.
The author you quoted never said the relativistic conditions would be continually varying to begin with. He said the relativistic conditions would require some type of correction on a continuous basis.
This is only true when the relativistic conditions are varying. Under constant relativistic conditions, you only need to make the initial correction, not continual corrections.
Your reply, despite mis-stating the claim, suggested that no continuing corrections would be needed, because there would be no continuous error to "correct" for, since "constant acceleration" would dictate cause the clocks to read the same after launch.
I'm not sure what you mean by "read the same", but the behavior of the clocks would be consistent after launch.
In hindsight, who knows what you even meant, or what problem you even thought you were addressing, I just took it as directed toward the issue raised, but perhaps that was a mistake.
If the connection is not clear to you, perhaps I can explain it further.
What "changes" would those be?
Changes in velocity.
Would "greater acceleration" make the clocks run the same, or would they just increase the complications involved in figuring out the exact amount of the necessary corrections in order to synchronize clocks?
From the Ohio State link above:
"Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion.
Further, the satellites are in orbits high above the Earth, where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly than those located further away (see the Black Holes lecture). As such, when viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.
The combination of these two relativitic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)!"
What do you mean by "only?" What else is it?
A scientific theory that makes predictions about the real world. The mini-formal-system part of SR is only a small part of the whole.
In what way does that "something else" make it different from euclidean geometry or newtonian mechanis?
Newtonian mechanics is not just the mini-formal-system of the three Law, either. On the ohter hand, Euclidean geometry makes no predicitons to test.
"Jury-rigged" or not, has his (and many others, including Lorentz) explanation been experimentally disproved?
Has Ptolemic astronomy been disproved? You can jury-rig the cosmos to fit the Ptolemic principles.
You apparently still seem to believe that the facts dictate that only a particular explanation can be advanced to account for them.
Do I?
"Jury-rigging" the theory is not the same as "jury-rigging" (misrepresenting) the facts to conform to your theory, ya know?
I would not call misrepresenting the data "jury-rigging".
Your first attempt to dismiss Van Flandern was to call him a crank.
Your next attempt was to say that his ideas had not disproved relativity ...
Now you throw out a perjorative term like "jury-rigging" rather than respond to the question. All quite predictable.
You have not pinted to any single significant experiment Van Flandern designed or conducted to establish his theory. You have given no reason to think his explanations are preferable. Instead, you just expect people to accept any possible position as having equal value and worth, regardless of how unproductive or even counter-productive it might be. All quite predictable, as well.
You don't analyze questions that might undermine your conclusions, ...
I don't know nearly enough about physics to form personal opinions on Van Flandern's work. As for questioning my conclusions on issues I do know something about, I do that regularly.
The thoughts of such geniuses notwithstanding, the "true" view must always be the one perceived as being held by the majority of present-day scientists, whether they are particularly brilliant, or not, I spoze.
Accumulated knowledge trumps the opinions of ancient sages. Galen was a brilliant man; would you want to be treated to his medicinal practices? That Einstein, Feynman, etc. were more rcent does not mean they can't be wrong about some things.
Well, sure, you can define any word any way you want to prove your argument.
My argument is how scientists, and in particular biologists, use the word. My definition is ireelevant.
When pushed, they will say that they believe that cancer is (or can be) caused by smoking, but that they are not really trying to insist that "smoking causes cancer" with the justification supposedly being that even the slightest increase in the "odds" of event x following event y "means" y causes x.
Actually, my understanding is that they are saying smoking has specific biological effects that often engender cancer formation. You are the only one insisting the relationship is strictly correlative.
In one aspect, relativity and euclid both define a "straight line" in the same way, i.e., as the shortest distance between two points. The difference is that for Euclid the two points in question were, by definition, in the same two-dimensional plane. In relativity, the shortest distance is in 3 dimensions, and is qualified by the word "possible."
Technically, it is in a two-dimensional manifold, which in a Euclidean cordinate system would be three dimensions.
Although I find the subject of relativity inherently interesting, my main purpose for discussing it in this particular thread involves the instructiveness it can provide with respect to concepts of "truth," "reality," epistemology, etc. I think you and I have major differences in the way we perceive what relativity reveals about the nature of truth, reality, scientific theory, etc.
That should make the discussion interesting.
Hmmm, where to start? I will come back to relativity later, I guess. Let's start with this:
One Brow said: "You have not pinted to any single significant experiment Van Flandern designed or conducted to establish his theory. You have given no reason to think his explanations are preferable. Instead, you just expect people to accept any possible position as having equal value and worth."
I don't really even understand your first sentence. If you read them, you will see that the Van Flandren articles I have cited, purport to list EVERY scientific experimented which is cited as "confirmation" of relativity. He then point out that (or at least claims) that the results of each of these also "confirm" (are not inconsistent with) Lorentzian relativity. Do none of these experments count unless Van Flandern personally designed and conducted them, is that the idea?
He (Van Flandern) has given reasons why he thinks his views are preferable (mainly dealing with saving the notion of causality) and I have quoted him (so in that sense you might say that "I" gave the reasons).
Whether they are indeed preferable, merely equal, or clearly inferior to alternative views is no doubt debatable, but evidently such debates cannot be settled on the basis of experimental evidence. If you prefer one over the other, I am asking you why--which you seemed to answer when you said it was a combination of more elegance and your conclustion that ONLY relativisitic assumptions could explain the facts. The last part of your claimed basis for preference is simply not shared by Carlip or any other person I know of, including Einstein.
One Brow said:
1. "That Einstein, Feynman, etc. were more rcent does not mean they can't be wrong about some things."
2. "The presence of a debater is not a guarantee of the legitimacy of Van Flandern's position."
3. "He concedes one issue about the speed of gravity propagation not being experiementally verified. This does not validate Van Flandern's claims about matter exceeding c."
These are but three recent examples of the type of "response" you offer repeatedly in our discussions. Your "responses" are utter non sequiturs, and I don't know why you bother to make them.
It's like me saying fire engines are red and you "responding" with "all things are not red!" I never said they were, nor even tried to suggest it. Why say it?
Furthermore, the extremism suggests a recurrent resort to all or nothing thinking on your part. You proceed as though if it is not "guaranteed" that your views may be wrong, and/or that if there is any possiblility, however remote, that your claims might be right, then they should be accepted as correct and "right."
View from another perspective, you simply seem to imply that if anyone who disagrees with you "could" be wrong, then that proves that you are right. Either way, the beginning and ending premise seems to be that: "*I* could not possibly be mistaken, although others can be. Only others make errors, not me."
There is a strong element of non-critical, subjective unilateralness in these types of responses, as I see it. Each and every such statement you make could easily be "levelled" against your position (which, of course, would be equally meaningless). For example:
1. "That contemporary physcists are more rcent does not mean they can't be wrong about some things."
2. "The presence of a debater is not a guarantee of the legitimacy of Carlip's position."
3. "Van Flandern concedes one issue about the speed of gravity propagation not being experiementally verified. This does not validate Carlip's claims about matter not exceeding c."
One Brow said: "They changed the rate of a clock tick, prior to launching the satellites, so that while in orbit the ticks in the clocks would be of the same length as those on earth."
I'm not sure the question of "ticks" is important to our disagreement here, but I aint 100% sure it aint, either, so let me address that issue before proceeding.
Assume you have two wrist watches. After a given duration of time, one of them has ticked 60 times, and it shows one minute elapsed. In that same duration, the other has ticked 61 times and shows 61 seconds elapsed. How can I synchronize them?
Many ways (and the fact that there are many ways has general relevance elsewhere, I think). One way would be to go into the clock which runs faster and adjust the mechanism which controls the degree the second hand on the watch moves with each tick. If I do this right, I can make it so that the second hand on that watch completes a 360-degree circle in exactly 61 ticks. Once this is done, the clocks will thereafter "agree" on what duration is to be measured and reported as "one minute." Note, however, that getting them to agree can in no way tell me if one was right and one was wrong, or even if both were wrong to some degree, prior to the adjustment. That doesn't matter to me. I don't care what a "real" minute is, I just want them to agree, that's all. Note also that one watch still ticks 61 times in what it calls "one minute," while the other only ticks 60 times.
Agreement could have been achieved in a number of other ways. For example, I could have adjusted the mechanism which makes the faster clock "tick' (assuming that there is such a mechanism in a wristwatch, which I dunno). If I could adjust that mechanism and slow it down to where the faster watch only ticks 60 times in the same duration in which it formerly ticked 61 times, I have acheived the same desired result: synchronization of the two watches.
It is my understanding that the GPS people used the first method of synchronization, not the second one. Either way, the clocks will always agree thereafter, barring malfunction. But, also, either way, had no adjustment been made, the "per minute" difference between the two watches would have persisted, and increased in magnitude with each passing minute. In other words, the difference, if uncorrected, would have been continous and increasing with time.
I asked: "What "changes" would those be?
You answered: Changes in velocity.
Before we go on, let me get a more specific response, OK? As I understand it, the term "velocity" is consists of two distinct components, i.e., speed and direction. Is that also your understanding?
If so, then what changes in the "velocity" are you talking about?
1. Changes in speed,
2. Changes in direction,
3. Or some component of change in each?
One Brow said: "Because the acceleration of the satellites is constant, there is no need to make continuing adjustments to the clocks."
The terminology about "constant acceleration" still appears to me to be one source of our disagreement (the use of the word "because" is another, but I'm not addressing that now). If an object is not changing in terms of either it's rate of speed or it's "direction," then it is not accelerating. It is simply in "uniform motion" and is therefore in an "inertial frame of reference" as I understand it. "Inertial," apparently, because at that point, its movement is governed strictly in accordance with newton's law of inertia. No forces are acting upon it, and it is proceeding on the basis of "inertia" alone. Neither it's speed nor it's direction will change unless and until an external force is "impressed" upon it.
As I pointed out in a prior post, within the parameters of relativistic theory, no object could ever be in "constant acceleration" with respect to its "speed" component. On the other hand, an object can constantly be changing direction. But then the question arises about what, exactly, constitutes a change in "direction?" Newtonian mechanics and relativistic theory give quite different answers to this question, as I understand it.
One Brow said: "Because the acceleration of the satellites is constant, there is no need to make continuing adjustments to the clocks."
Ignoring the "because" aspect of this statement for the moment, the accuracy of the claim that "there is no need to make continuing adjustments to the clocks" is neither right nor wrong in itself. That is strictly dependent upon other factors. If the clocks have previously been adjusted to offset for the effects of what you are calling "constant acceleration" then, right, you don't need to do it twice. If it hasn't been, then continous adjustments will still have to be made (or one adjustment, which has a continuing cancelling effect, which is basically the same thing).
Your initial claim seemed to be that the "constant acceleration" dispensed with the need for any pre-launch adjustments whatsover which would alter time-keeping once orbit was reached. You are still claiming that now, best I can tell, since you are still referring to "constant acceleration" as the reason for having clocks that agree.
One Brow said: "Because the acceleration of the satellites is constant, there is no need to make continuing adjustments to the clocks."
Assuming there is "constant acceleration," onther questions would still remain. Constant with respect to who (what)? The author who brought this up said that was the question, and that the "answer" to this raised doubts among relativists themselves about whether GPS would work. That same author acknowledged the 38 microsecond pre-launch adjustment, but that wasn't the problem he was even addressing. To repeat:
"Van Flandern reports that an intriguing controversy arose before GPS was even launched. Special Relativity gave Einsteinians reason to doubt whether it would work at all....In (Einstein) theory, however, it was expected that because the orbiting clocks all move rapidly and with varying speeds relative to any ground observer (who may be anywhere on the Earth’s surface), and since in Einstein’s theory the relevant speed is always speed relative to the observer, it was expected that continuously varying relativistic corrections would have to be made to clock rates. This in turn would have introduced an unworkable complexity into the GPS. But these corrections were not made. Yet “the system manages to work, even though they use no relativistic corrections after launch,” Van Flandern said. “They have basically blown off Einstein.”
The "speed" at which satelites move may be constant with respect to once fixed point, such as the earth's center of gravity. But the concern apparently was that not all earth-bound observers are at one fixed point (be it the center of gravity or any other point). For this reason, time and distance would have to perceived differently for different observers if their measured "speed" of the satellites was to constant for all of them.
As I understand it, the solution to this problem was to sidestep the question of what the earth-bound observers' individual clocks would read, and instead achieve an "agreement" by reference to other satelites.
As I said before, they "blew-off" Einstien in perhaps a limited (and probably misleading in the context this author put is) sense. They simply made an end-around and GPS does not require and satellite/observer comparison, given it's design.
"Constant acceleration" is a bit of an oxymoron, ya know? Heraclitus said that the only thing which remains constant is change itself. Likewise, the only thing "constant" about "constant acceleration" is change itself--there is no other "stability" to it.
One Brow said: "Do you think cranks exist? Is there something about Van Flandern's work that distinguishes it?"
Since SR appeared in 1905, many eminent scientists have doubted it (and I don't just mean in the first decade or so after it was promulgated) and many still do. Van Flandern's paper was peer-reviewed, and his resume (http://www.metaresearch.org/home/about%20meta%20research/resume.asp) does not lend any credence to a claim that he is just a "crank." Absent some reliable report that Van Flandern has been pronounced to be mentally unstable by a person qualified to make that judgment, I see no reason to conclude that he is a crank just because one or more (perhaps mentally unbalanced themselves) person(s) make a career of calling him one (see quote below). As a matter of fact, I see it as being rather presumptous for a laymen to criticize the "knowledge" of relativity that a man with Van Flandern's education, experience, and production possesses.
"Tom extensively debated the speed of gravity in several scientific journals and on Usenet with a relativist named Steve Carlip. Carlip as near as I can tell is a reasonable fellow who strongly disagreed with Tom but was civil and professional (and revised some of his arguments as a result of discussions with Tom). However, some observers of this discussion were less civil and one in particular, Chris Hillman, was downright malicious. He maintained a site with extensive content dedicated to discrediting Tom..."
http://www.gonzoscience.com/GonzoUSA/?page_id=1508
Here Van Flandern articulates a point I have repeatedly tried to make, which, in essence, is the one Asimov also made in the wiki article I cited in another thread:
"Today, many physicists and students of physics have acquired the impression that these two SR postulates have been confirmed by observations. However, that is not the case. In fact, none of the eleven independent experiments verifying some aspect of SR is able to verify either postulate. Indeed, no experiment is capable of verifying these postulates even in principle because they become automatically true by convention if one adopts the Einstein clock-synchronization method, and they become just as automatically false if one adopts a different synchronization convention such as the “universal time” postulate of Lorentz."
http://metaresearch.org/cosmology/gravity/LR.asp
Does that make sense to you, Eric? Do you agree with it?
In this same article, Van Flandern elaborates upon what he meant when claiming GPS "blew off Einstein:"
"GPS [synchronizes] each clock (in epoch and rate) to an imaginary, moment-by-moment co-located clock always at rest in the local gravitational potential field, the Earth-centered inertial frame. But that is precisely what LR specifies as the method of synchronizing to Lorentzian universal time...the GPS system has been designed to use Lorentz synchronization, for which one frame, the local gravity field or ECI, is special; not Einstein synchronization, wherein clocks tick at their natural rates and all inertial frames are equivalent. By itself, this does not prove LR “right” or SR “wrong”. But the practical difficulties for GPS of not changing the natural rates of clocks pre-launch, or with the use of SR for any frame other than the Lorentzian preferred frame, are very great."
Do none of these experments count unless Van Flandern personally designed and conducted them, is that the idea?
Count as what? Why should they confirm Lorentzian relativity over SR? Is "not inconsistent with" the same as "being a prediction of"?
which you seemed to answer when you said it was a combination of more elegance and your conclustion that ONLY relativisitic assumptions could explain the facts.
Only SR/GR explain the eviddence without jury-rigging, with elegance. Any system can be jury-rigged to explain the evidence.
The last part of your claimed basis for preference is simply not shared by Carlip or any other person I know of, including Einstein.
If you don't think Einstein preferred elegant solutions over jury-rigged ones, I submit you don't understand him at all.
1. "That Einstein, Feynman, etc. were more rcent does not mean they can't be wrong about some things."
2. "The presence of a debater is not a guarantee of the legitimacy of Van Flandern's position."
3. "He concedes one issue about the speed of gravity propagation not being experiementally verified. This does not validate Van Flandern's claims about matter exceeding c."
These are but three recent examples of the type of "response" you offer repeatedly in our discussions. Your "responses" are utter non sequiturs, and I don't know why you bother to make them.
You mean when you snip a sentince out of context, it can sound like a non-sequitur? Holy quote-mines, Batman! You said that thinkers in the first part of the 20th century did not share a view no common among physicists, so my response was that the accumulated knowledge of science is more reliable than the thought of individuals of prior years, whether 2000 or 100 years ago. It was directly on that point. You offered the presence of the debates with Carlip as evidence the position of VanFlandern was legimate, I disputed that point. You offered a position the the speed of gravitational propagation has not been measured as evidence for Van Flandern's position generally. Open questions do not support "alternative" science.
Furthermore, the extremism suggests a recurrent resort to all or nothing thinking on your part.
Sorry, but this sort of comment, and the ones that follow, is difficult to take seriously, especially after you went out of your way to take my comments out of context to make them look extreme. We have each conceded on a number of points over the years, too many for either of us to pull out the extremist card on the other.
1. "That contemporary physcists are more rcent does not mean they can't be wrong about some things."
Absolutely true. I have no doubt contempory physicists are wrong about many things.
2. "The presence of a debater is not a guarantee of the legitimacy of Carlip's position."
Absolutely true.
3. "Van Flandern concedes one issue about the speed of gravity propagation not being experiementally verified. This does not validate Carlip's claims about matter not exceeding c."
Absolutely true.
It is my understanding that the GPS people used the first method of synchronization, not the second one.
I can accept that. It probably doesn't make much difference.
Before we go on, let me get a more specific response, OK? As I understand it, the term "velocity" is consists of two distinct components, i.e., speed and direction. Is that also your understanding?
You mean, like water consists of two distinct components?
On the other hand, an object can constantly be changing direction. But then the question arises about what, exactly, constitutes a change in "direction?" Newtonian mechanics and relativistic theory give quite different answers to this question, as I understand it.
You have a point there. If the GPS satellites are merely following time geodeisics (and this seems plausible to me), then they awould not be under acceleration in GR. I was possibly mistaken to apply the Newtonian idea of acceleration to the question.
As I said before, they "blew-off" Einstien in perhaps a limited (and probably misleading in the context this author put is) sense. They simply made an end-around and GPS does not require and satellite/observer comparison, given it's design.
Since the relative motion of the satellites to each other would be constant, that could work.
One Brow said: "Do you think cranks exist?"
You didn't answer that question.
As a matter of fact, I see it as being rather presumptous for a laymen to criticize the "knowledge" of relativity that a man with Van Flandern's education, experience, and production possesses.
Unfortunately, in here there is only you and I, so we'll have to make do.
http://www.gonzoscience.com/GonzoUSA/?page_id=1508
"Van Flandern attempted to establish a common set of principles among alternative cosmologists."
"In Van Flandern’s view, requiring extraordinary proof weeded out some extraordinary ideas that were true but which had only ordinary proof ."
"Van Flandern argued that a greater reliance on deductive reasoning could help science avoid many of the pitfalls he had identified."
A century ago, in the midst of overturning all the cherised ideas of physics, no one formed a group of "alternative" physicists. While the points of view of the neo-Darwinists were under attack, no one identified themself as an "alternative" biologist. The revolutionary work was done by physicists and biologists. Even in praising Van Flandern, they condemn him. Do you think it's right to accept extraordinary ideas in science on ordinary proof? Do you think that might lead to an inabiltiy to distinguish between the remarkable and the coincedental? You've already been saying science is essentially deductive in character, do you think it should be more so?
Does that make sense to you, Eric? Do you agree with it?
I'm not sure what the clock-synchronization method refers to, unless he means that SR assumes that time can change and LR that only clocks change. While I was there, I did note the following quotes:
"And that, in brief, is why there is no universal speed limit in LR – nothing ever happens to time itself, just to certain types of clocks attempting to keep time. Such clocks might malfunction or stop operating altogether at speeds at or above the speed of light. But there is no slowing of time to prevent reaching such speeds. And other types of clocks exist for measuring time unaffected by speed or potential, just as many types of clocks are unaffected by temperature."
"However, only an experiment demonstrating a real phenomenon propagating faster than light in forward time could decide between SR and LR."
Is there some way these two points are not in opposition? If you can build a clock that does not experience the effects of SR, I would think that would discredit SR.
”But the practical difficulties for GPS of not changing the natural rates of clocks pre-launch, or with the use of SR for any frame other than the Lorentzian preferred frame, are very great."
Do you agree with that?
If this account is correct, then Van Flandern's "crank" theory led him to boldly predict a variety of things that have subsequently been confirmed.
Is the exploded planet hypothesis (or theory) in any way connected to LR?
On that criterion, based on the little I have read by him, I see no reason to think he is merely a "crank." Quite the contrary. He may be right or wrong, but he seems reasonable and far from "extreme" in the articulation of his viewpoints.
So, you use "crank" as an identifier of people who are unreasonable and extreme in their views?
One Brow said: "offered the presence of the debates with Carlip as evidence the position of VanFlandern was legimate, I disputed that point."
No, you did not "dispute" it, in my book. If you want to "dispute" the legitimacy of Van Flandern's position (it is quite legitimate, and generally conceded to be so as far as I can tell), feel free. If I claim an object is red, and you disagree, you can have it spectro-analyzed, or whatever you want. It adds nothing to say that "it's not red just because you claim it is." That's too trivial and obvious to be meaningful, and the reverse is just as true. I can say to you: "it's not non-red just because you say it is." Neither statement adds or subtracts anything from the validity of either position, it merely goes without saying.
One Brow said: "Count as what? Why should they confirm Lorentzian relativity over SR? Is "not inconsistent with" the same as "being a prediction of"?"
They don't confirm LR "over" SR, and are not claimed to. The point is that they don't confirm SR "over" LR, either, can't you see that? The point, I mean?
If SR "predicts" the outcome of experiment A, then LR also "predicts" it. We have already discussed the nature of "prediction" in the context of scientific theory. In that context, a "prediction" is merely a necessarily logical implication of the premises chosen. It is not a form of clairvoyance. I know you tend to see it otherwise, but, yes in science "confirmation" basically reduces to "not inconsistent with" so long as the confirming event would be necessarily implied by your premises.
That a2 + b2 = c2 in a two dimensional plane is a "prediction" of euclidean geometry as it regards right triangles. If you want to "confirm" it, go measure a right triangle. If two different theories predict the same outcome, then, while the occurence of the predicted outcome "confirms" both, it distinguishes neither from the other.
Again, the recurring unilateral "logic" you seem to be applying here is that unless a "confirming" experiment can be said to favor LR "over SR (which would disconfirm SR), then ONLY SR is confirmed. The "point" can be easily reversed: Ican just as easily claim that ONLY LR is "confirmed," and SR is therefore thrown into doubt, if the two predict the same outcome, if that is my standard (which is not really a "standard," it is just a convenient and opportune way of re-asserting my initial prejudice--that SR is to be preferred over LR, or vice versa).
One Brow said: "Open questions do not support "alternative" science." Nor do they create "established" science. Open questions merely leave room for theoretical alternatives, all of which may be wrong.
Bo Diddley writ a tune (later covered by Eric Clapton and many others) called "Before ya "cuse me" (take a look at yourself). I would suggest that before you so readily conclude that a point you advance to "prove" your viewpoint in fact does so, you first ask:
1. Would this same point, if relevant, also undermine my own viewpoint, and
2. Does it actually do anything substantial to cast doubt on viewpoint I'm attacking?
I suggest that the "point" consisting of "Open questions do not support "alternative" science" cannot pass either test.
One Brow asked: "Is there some way these two points are not in opposition?"
Yeah, I think there is. Superficially they are in opposition, but they are not the same type of claims. In the first claim Van Flandern is enthusiastically articulating (and endorsing) the premises underlying his preferred view (and, given that passage alone, would appear to be extremely dogmatic). But here he is merely playing the role of advocate, not pretending to be the final arbiter of truth.
In fact, in the second passage, he is revealing the perspective from which his first claim was made (that of advocate) and acknowledges that experiment has not decided the issue. Of course later he makes a more important point, i.e., that you cannot use experiments which simply assume and incorporate your premises, ab initio, to "prove" your premises.
Van Flandern said: But the practical difficulties for GPS of not changing the natural rates of clocks pre-launch, or with the use of SR for any frame other than the Lorentzian preferred frame, are very great."
You asked: Do you agree with that?
Yeah, given my limited understanding of the issues and of what he is saying, I do.
In effect he is saying that, in the circumstances surrounding GPS, at least, application of a Lorenztian transformation is much simpler than the relativistic one, which would require much more complex calculation, and much more (presumably accurate) raw data, to implement. As he says, this in no way proves one over the other, but, from a strictly practical viewpoint, LR is immensely preferable, in this case.
One Brow said: "Do you think cranks exist?...So, you use "crank" as an identifier of people who are unreasonable and extreme in their views?
I don't know what "crank" is supposed to be, exactly. I haven't even looked for a dictionary definition. I don't think it matters much in this context. It is, primarily, a pejorative term designed to discredit (via ad hominem argument) an opponent.
I didn't answer the question about whether "cranks" exist for both of those reasons. I'm not sure what a crank is, for one, but, more importantly, because the question is purely rhetorical. Whether or not horses and buggies "exist" says nuthin about whether or not my '53 Ford pick-up truck is a "horse and buggy."
One Brow said: "Do you think it's right to accept extraordinary ideas in science on ordinary proof?"
I can see both sides of that issue, and I don't think there is a single, simple answer. If an "extraordinary view" is simply one which is not currently favored, then, yeah, in general, I sympathize with the sentiment being expressed by Van Flandern. Why should any additional inherent weight be given to an established, favored view, just because it is popular or commonly accepted? Better to judge each view on it's merits, whether the choice is between aristotlean metaphysics and the metaphysics of "naturalism;" between helio-centric and geo-centric premises; between newtonian and relativistic views of gravitation and mechanics, or whatever.
By that very same token, there is no reason to accept an "extraordinary" idea in favor of an "ordinary" one, just because it is "extraordinary." Ultimately it seems that the issue of whether an idea is ordinary or extraordinary is completely irrelevant to it's merit, which must be judged by other standards.
Giving excessive weight to the established view is simply institutionalized prejudice, really. At one time it was an "extraordinary" view, for example, that blacks should be entitled to the same rights as whites. But that in no way affects the (inherent, as opposed to subjective) value of the respective arguments for and against each view.
Hand-waving is simply not a good "argument," without respect to the viewpoint it is intended to "buttress."
No, you did not "dispute" it, in my book. If you want to "dispute" the legitimacy of Van Flandern's position ...
The point I meant was the legitamcy of any position being supported by the notion of there being a debate.
They don't confirm LR "over" SR, and are not claimed to. The point is that they don't confirm SR "over" LR, either, can't you see that? The point, I mean?
Yeah, I get that.
Nor do they create "established" science. Open questions merely leave room for theoretical alternatives, all of which may be wrong.
Exactly.
I suggest that the "point" consisting of "Open questions do not support "alternative" science" cannot pass either test.
I submit a third criterion, "Does it show the evidence being used is insufficient to prove a point?". It seems very antagonistic to assume that a claim something is not evidence for one side means must be evidence for the other side. Why would you think that?
One Brow said: "Even in praising Van Flandern, they condemn him."
I don't see the condmenation. Let's suppose Van Flandern has a somewhat unique (among grant-supported academics, at least), inclination to pick-up long-ignored alternative theories and to then subject them to an independent analysis to see if there are adequate reasons for rejecting them. So what? Isn't this, too, a valid and admirable approach to "science?" Shouldn't valid criticism of established theories be welcomed, rather than shunned? Should all "scientists" confine their activities to seeking justifications for prevailing theories only? I mean, a scientist is of course free to do just that if he wants, but is apologetics somehow inherently preferable to dissent?
As he says, this in no way proves one over the other, but, from a strictly practical viewpoint, LR is immensely preferable, in this case.
Was this the solution used, if it was so much simpler?
I don't know what "crank" is supposed to be, exactly. I haven't even looked for a dictionary definition. I don't think it matters much in this context. It is, primarily, a pejorative term designed to discredit (via ad hominem argument) an opponent.
Is it directed at the opponent fo the argument? Are there people who are cranks in one field and exerts in another?
Whether or not horses and buggies "exist" says nuthin about whether or not my '53 Ford pick-up truck is a "horse and buggy."
However, if you say there never was such a thing as a horse-and-buggy, you are unlikely to be convinced merely by seeing an equine hooked up to a cart.
Why should any additional inherent weight be given to an established, favored view, just because it is popular or commonly accepted?
I agree.
Ultimately it seems that the issue of whether an idea is ordinary or extraordinary is completely irrelevant to it's merit, which must be judged by other standards.
Do the standards involved change depending on the ordinariness of the claim? Would you be more willing to believe a Fox News complaint that Obama bowed to a Japanese minister than one one where Obama was seting up concentration camps for Christians? Are you the knee-jerk skeptic who never believes anything, or the guy who believes everything? If neither, what are your standards for the difference between what you do and do not believe, generally?
Giving excessive weight to the established view is simply institutionalized prejudice, really. At one time it was an "extraordinary" view, for example, that blacks should be entitled to the same rights as whites.
Why would that view be extraordinary? Do you think extraordinary means "rare"?
One Brow said: "I submit a third criterion, "Does it show the evidence being used is insufficient to prove a point?". It seems very antagonistic to assume that a claim something is not evidence for one side means must be evidence for the other side. Why would you think that?"
I DON'T think that, and that's what I'm saying in all these posts on the topic. I reject your third criterion as being in any way substantial, that's my point. It adds nothing, as does the "argument" that: "Just because we haven't detected little green men living underground at the center of mars doesn't prove they aren't there" in response to your assertion there is no evidence for such a claim. No evidence is EVER sufficient to PROVE anything in empirical science, so the asserting it is meaningless.
Simply asserting that X "does not prove" Y is empty. Arguing that "X lends no credence to, and provides no evidence whatsover in support of, Y, and here's why..." is, of course, an entirely different matter.
Shouldn't valid criticism of established theories be welcomed, rather than shunned?
"Valid" being the key word. What criticisms of Van Flandern's were valid?
I am glad that we agree the third criterion, with your offered correction from "prove" to "provides no evidence for", is valid.
Similarly, a claim that "X can perhaps be seen as some evidence in favor of Y, but it is insufficient to establish it in this case because...." would presumably have (depending on what is inserted after the word "because") some substance and relevance to the claim being disputed. But even then, it might be little more than a straw man argument unless the party being responded to had first asserted that a particular piece of "evidence" was, in itself, sufficient to establish his claim.
One Brow said: "One Brow said "Valid" being the key word. What criticisms of Van Flandern's were valid?"
I wasn't addressing Van Flandern, or any of his claims, in particular. But, let me ask you: which one's werent valid? I mean you must have something in mind, eh?
One Brow said: "Is it directed at the opponent fo the argument?" The answer to that question is self-evident to me, is there some ambiguity for you?
1. Van Flandern is (or is considered by some to be) a crank
2. This particular argument of Van Flandern's is inherently flawed and the way in which he tries to defend it is "crankish."
Which one, above, is addressed to the man, qua man, and which one is addressed to the substance of a particular argument? If you can't tell, I don't think there's much I could say to help you.
Suppose I'm a defendant in criminal case and I choose to testify in my own defense. I start out as follows...
1. First of all, let me assure you that I didn't commit this crime.
Response: that doesn't prove you're telling the truth.
2. Secondly, I was in another State at the time in occurred.
Reponse: your mere words don't prove that
3. And I can prove it.
Response: Just because you say you can prove it doesn't mean you can, and, even assuming you can, that wouldn't prove that you weren't implicated in, and responsible for the crime, by planning it and hiring someone else to commit it
I can go on for 1000, or 1,000,000 statements and, for each and every statement a "that alone doesn't prove..." response can be accurately given. So what?
I asked, so what? Well, for some, I guess the "so, what" might add up to this. The guy is obviously guilty because, for each and every statement he made, it was easy for me to "dispute" and "refute" it.
One Brow asked: "Do the standards involved change depending on the ordinariness of the claim? Would you be more willing to believe a Fox News complaint that Obama bowed to a Japanese minister than one one where Obama was seting up concentration camps for Christians?"
The question was about sufficient evidence, not about what claims, unsupported by any particular evidence whatsover, I would be more willing to accept "on faith."
One Brow asked: Why would that view be extraordinary? Do you think extraordinary means "rare"?
Without worrying about possible connotations, the word simply denotes "out of the ordinary," as I understand it. In the beginning of that post, I presented a working definition of "extraordinary" for the purposes of my comments.
One Brow said: "Was this the solution used, if it was so much simpler?"
According to Van Flandern, yes. As I already said, given my limited understanding of the issues, and of what he is saying, it sounds right, at least if his claims are true. Needless to say, I am simply assuming that Van Flandern is not just outright lying about what was done, in fact.
Keep in mind that the "R" in LR stands for "relativity." Nobody questions that relative differences will appear. The debate is about the source and "cause" of the relative difference.
If I saw Obama come on TV and announce that in exactly 7 days he was gunna nuke Iraq back into the stone-age, one of my first thoughts might be to make sure that this wasn't a satire, or comedy or something. Then I might want to confirm that this TV appearance wasn't just the product of someone "hacking" into my TV reception, etc.
But, if, upon investigation, I concluded that he said it, I would take that statement as prima facie evidence that he meant it (although it could all just be a calculated bluff, of course). What I would not do is say: "That HAS to be comedy. That HAS to be a spoof. He would NEVER say that, so there is no need to even invesigate whether he "really" did say it, or not. I already know he wouldn't, because I know Obama, and the Obama I know wouldn't say it."
One Brow said: "The point I meant was the legitamcy of any position being supported by the notion of there being a debate."
Well, I can understand that that could have been an issue that you might have been interested in addressing, but you didn't.
The fact that an established, respected, busy scientist is willing to spend 2-3 years debating an issue with someone does not, of course, "prove" that either one is, or is not, a crank, but it does suggest that the alleged "crank" is being taken seriously. Had you responded with "Yeah, and ya know what? Carlip thinks he's a crank too," that would certainly be relevant as a way of countering the superficial appearance.
In any event, mentioning the debate with Carlip was never presented by me as being the "only," in-and-of-itself, evidence that Van Flandern might not be a crank, nor were my comments presented, even when considered together with other evidence, as being "proof" that Van Flandern is not a crank.
With respect to Carlip, the more important aspect is that he (Carlip) spents years analyzing and debating the actual ideas of Van Flandern with Van Flandern himself. He would be in a much better position to spot Van Flandern as a "crank" than you, I, or probably anyone else you had in mind when insinuating that his "crank" was known. By "actual ideas" here, I don't mean the perhaps "unpopular" conclusions they lead to (which conclusions alone are more than enough for many to allege that others are "cranks," denialists, or whatever).
One Brow said: "Only SR/GR explain the eviddence without jury-rigging, with elegance. Any system can be jury-rigged to explain the evidence."
Perhaps you would care to define "jury-rigging" and explain the way in which LR has been "jury-rigged," eh?
Me: One Brow molests children.
One Brow: What evidence do you have for making that claim?
Me: So, you admit it, eh?
One Brow: No.
Me: Then why would you even ask me how much evidence I had.
One Brow: Just curious about why you would even make such an absurd allegation.
Me: I heard it on the street. Now prove ya aint no child molester.
One Brow: Why should I even try?
Me: So, ya can't, eh? That's exactly what I thought.
In one of his early Texas political office campaigns, LBJ told his campaign manager that he wanted to get the word out that his opponent fucked sheep.
His manager said: Lyndon, we both know that isn't true.
LBJ: Well sure, we know that, and so will most people who hear it. That's not even the point. I just wanna see the S.O.B. deny it, ya know?
To address the theoretical scientific issue briefly, let's look at special relativity.
Without going into details, Einstein basically said: The measurment we get for the speed of light will always be independent of the the speed of both the source and the reciever of the light signal (at least in frames of reference which are maintaining a uniform speed in a "straight line").
OK, now what? How can we measure the speed to be the same whether we are approaching or going away from the source at a speed of, say, .999c? How is that possible? Simple, says Einstein: we just change our units of time and distance accordingly. What might "seem" to be a million miles away if we are approaching it might "seem" to be 100 million miles away if we are going away from it. Likewise, what might seem to be a minute in one context might seem to be a year in the other.
An "elegant" solution, eh, kinda like Plato's world of forms which showed why all transient things were "mere appearances" and illusion. Does this "solution" transmute the formerly abstract notions of "time" and "space" (distance) into "real" physical things which can be bent, distorted, and changed at will? Sure, so what?
Well, suppose we didn't assume those things, then what? Well, then the time and distance would be constant, but the speed of light could vary. We wouldn't want that, now, would we?
Well, I guess not, if you say so. You're the genius here, after all.
It's not because I "say so," it's because that's how we actually measure it.
Well, is there any other reason we might "measure it" that way, even if it isn't really true?
Einstein: Sure, but those reasons aren't as elegant as mine, see?
It may seem kinda ironic that some people object to replacing Newtonian notions, supplemented by Lorentzian relativistic transformations, with special relativity on the very same grounds that Einstein later opposed QM--he didn't think you could simply dispense with fundamental notions of causality. Although QM might "work," it could not actually represent the true underlying metaphysical reality of the situation.
I guess it all depends on whose ox is being gored, eh? When it came to his own theories, Einstein had no problem with saying "forget about reality." Whether what we measure to be a yard is "really" a yard or "really" two yards is totally irrelevant. The only relevant thing is what we measured it to be.
But, let me ask you: which one's werent valid?
One thing I read up on is the claim that if the speed of gravity propagation is c, the Earth's orbit would be unstable. This was not true, the speed being c is actually very compatible with stable orbits.
You turn. Which of Van Flandern's criticisms do you think are valid?
1. Van Flandern is (or is considered by some to be) a crank
2. This particular argument of Van Flandern's is inherently flawed and the way in which he tries to defend it is "crankish."
Which one, above, is addressed to the man, qua man, and which one is addressed to the substance of a particular argument? If you can't tell, I don't think there's much I could say to help you.
The term crank refers to ideas and opinions within a specific field, and is directed at the opinions expressed by the man. Many cranks are brilliant, competent men in a different field. Bill Maher is a great example of a good comedian adn medical crank. No doubt Van Flandern was extremely capable in many ways, even though he seems to have been a relativity crank.
The guy is obviously guilty because, for each and every statement he made, it was easy for me to "dispute" and "refute" it.
Being able to dispute it is not being able to refute it, and the presumption in the trial is supposedly toward innocence, not guilt.
The question was about sufficient evidence, not about what claims, unsupported by any particular evidence whatsover, I would be more willing to accept "on faith."
If the first complaint is accompanied of by a picture of Obama bowing, ane the second by picture of some people being detained?
In the beginning of that post, I presented a working definition of "extraordinary" for the purposes of my comments.
By extradinary in the sense of the saying "extraordinary claims require extraordinary evidence", I do not beleive popularity is the standard of ordinary.
According to Van Flandern, yes. As I already said, given my limited understanding of the issues, and of what he is saying, it sounds right, at least if his claims are true. Needless to say, I am simply assuming that Van Flandern is not just outright lying about what was done, in fact.
Actually, you referred to his take on the solution for GPS satellites as misleading.
Had you responded with "Yeah, and ya know what? Carlip thinks he's a crank too," that would certainly be relevant as a way of countering the superficial appearance.
I don't believe you, frankly. You have never been willing to accept the opinions of mainstream biologists when it comes to saying intelligent design is crankish, and instead say that the mainstream biologists have been pushing a specific paradigm and want to weed out opposing thought. I find it very difficult to believe that, if I were to go looking into the Van Flandern-Carlip correspondence and found statements where Carlip said Van Flandern didn't know what he was talking about, you would interpret that in any way other than some mainstream physicist trying to enforce orthodoxy.
In any event, mentioning the debate with Carlip was never presented by me as being the "only," in-and-of-itself, evidence that Van Flandern might not be a crank, nor were my comments presented, even when considered together with other evidence, as being "proof" that Van Flandern is not a crank.
Fair enough, I may have taken them wrongly.
With respect to Carlip, the more important aspect is that he (Carlip) spents years analyzing and debating the actual ideas of Van Flandern with Van Flandern himself. He would be in a much better position to spot Van Flandern as a "crank" than you, I, or probably anyone else you had in mind when insinuating that his "crank" was known.
So, do you trust the likes of Jeffrey Shallit in saying William Dembski's CSI is, basically, crankish? Wesley Elsberry on Intelligent Design? etc.
By "actual ideas" here, I don't mean the perhaps "unpopular" conclusions they lead to (which conclusions alone are more than enough for many to allege that others are "cranks," denialists, or whatever).
Do you think it's ever justifiable to suspect a thought process is crankish based on the conclusion? How about if the conclusion is that the earth is disc-shaped and less than 200 miles deep?
Perhaps you would care to define "jury-rigging" and explain the way in which LR has been "jury-rigged," eh?
With regard to LR, this is what I have read about it from physicists.
Well, is there any other reason we might "measure it" that way, even if it isn't really true?
If LR really worked as well as SR in explaining things, there would be a large LR community among physicists, and they would not be "alternative" cosmologists.
One Brow said: "Actually, you referred to his take on the solution for GPS satellites as misleading."
One paper, by another author, which I cited quoted Van Flandern, but did so in a way that I would call potentially, if not actually, misleading. I didn't say Van Flandern's statement's on the topic were misleading. I didn't say his "take" was misleading, which it is not, the best I can tell.
"Had you responded with "Yeah, and ya know what? Carlip thinks he's a crank too," that would certainly be relevant as a way of countering the superficial appearance.
One Brow said: I don't believe you, frankly.
What's not to believe? That I wouldn't think it was "relevant?" It would be, it would be on point, and it would be addressed to the issue we were discussing.
I didn't say I would automatically take anyone who called Van Flandern (or anyone else for that matter) a crank their word. Had Carlip called him a crank, based on years of correspondence, that would carry a lot more weight than some who never even read his work, but just didn't like his conclusions, for example.
One Brow said: "Do you think it's ever justifiable to suspect a thought process is crankish based on the conclusion? How about if the conclusion is that the earth is disc-shaped and less than 200 miles deep?"
Suspicion in one thing, outright accusation is another. No one can be sued for libel for mere suspicion, as far as I know.
One Brow said: "If LR really worked as well as SR in explaining things, there would be a large LR community among physicists, and they would not be "alternative" cosmologists."
What do you mean by "worked as well?"
"Test theories of special relativity are frameworks, which are used for examinations about the validity of Lorentz symmetry and the existence of a preferred frame of reference. They are flat space-time theories which differ from special relativity by having a different postulate about light concerning one-way speed of light vs two-way speed of light. Different postulates on light result in different notions of time and simultaneity...
[One such test theory] is the Mansouri-Sexl theory (1977) created by Reza Mansouri and Roman Ulrich Sexl[3] which is equivalent to Robertson's theory[4]...
Sexl/Mansouri spoke about the "remarkable result that a theory maintaining absolute simultaneity is equivalent to special relativity." They also noticed the similarity between this test theory and Lorentz ether theory of Hendrik Lorentz, Joseph Larmor and Henri Poincaré...However, Sexl/Mansouri preferred SRT over an ether theory, because the latter "destroys the internal symmetry of a physical theory".
http://en.wikipedia.org/wiki/Test_theories_of_special_relativity
You still seem to think that SR has somehow been "proven" over LR. In certain instances, it may be easier for mathematicians to use SR than LR (just as in many cases it is easier--and accurate enough-- to use Newtonian physics rather than relativity. On the other hand, I have seen it claimed that in many cases using LR greatly simplifies the mathematical process, with the same results.
I don't know what you mean by "works," but, the real question here was why you think that one is "true" and the other isn't. You get the same results either way. The main difference between SR and LR is philosophical/metaphysical, each takes a different view of what is "really" happening. If one doesn't care which one, if either, is real, then there is no reason to care or debate that issue. Just use the theory that's most convenient for your purposes (against, compare the current use of strictly newtonian notions, "blowing off" Einstein, for many practical problems).
One Brow said: "Do you think it's ever justifiable to suspect a thought process is crankish based on the conclusion? How about if the conclusion is that the earth is disc-shaped and less than 200 miles deep?"
To suspect, let alone conclude, that someone someone with a perfectly reasonable and supportable conclusion is a "crank" is simply a way of trying to support your position by illegitimate methods.
Calling anyone who doesn't agree with you a "crank," a "denialist," an "idiot," or whatever else comes to mind is a frequently observed phenomenon, but that doesn't make it admirable or acceptable. It generally tells me a lot more about the accuser than the accused.
One Brow said: " find it very difficult to believe that, if I were to go looking into the Van Flandern-Carlip correspondence and found statements where Carlip said Van Flandern didn't know what he was talking about...
Does an error make one a crank? I trust that, even assuming that Carlip thought Van Flandern made mistakes at times (which no doubt both did think of the other along the line), he showed him how and why he thought so. In other words, he would say "You're wrong there because (X, Y, and Z) and not simply "You're wrong there because you are a crank."
The way you use introduce the epithet to the consversation is to suggest that X is wrong BECAUSE HE IS A CRANK, without even addressing the issue in question. It's very platonic, what you do, ya know?
One Brow said: "You have never been willing to accept the opinions of mainstream biologists when it comes to saying intelligent design is crankish, and instead say that the mainstream biologists have been pushing a specific paradigm and want to weed out opposing thought."
You apparently misunderstand my position on intelligent design, but, no, I wouldn't call it "crankish," per se. There may be some bona fide cranks who advocate it, I dunno, just like there may be some bona fide cranks who espouse mainstream evolutionism.
There is so much extreme invective thrown around in that debate, much by scientists who might be quite reasonable in other settings, that I don't pay attention to any of it. I generally don't, anyway.
If someone has an authoritative argument for or against a given position, I may read and respect that. Their "opinion" about the mere "idiocy" or other alleged mental deficienicies of their opponents does not affect my opinion in the least.
It's actually the opposite for me: the more routinely vociferious one is in denouncing those who oppose his views, the less I trust his opinon, his judgment, his objectivity, and his confidence in his own opinion.
One Brow said: "Van Flandern was extremely capable in many ways, even though he seems to have been a relativity crank."
A "crank" whose article on the speed of gravity passed peer review, eh? I see. Did you even read it, I wonder, or just know it wasn't worth reading, due to the crank status of Van Flandern?
I recall seeing an article in Salon, the left-wing publication, that attempted to equate "anti-relativists" with "creationists" and condemn them as motivated by right wing politics. Is this where you get your impressions, I wonder?
Just how is it that he "seems to have been a relativity crank?" On the topic of relativity in particular, I mean?
"it is inevitable that Van Flandern's competence would be criticized because in 1990 he founded an organization, Meta Research, specifically to examine anomalies and puzzles that challenge mainstream theories. The Meta Research web site [14] is filled with reports on puzzles solved conventionally, but also with anomalies that stand up to scrutiny and demand theory revision or outright rejection. Van Flandern's strength is that he addresses all challenges head on and has answers that satisfy neutral observers."
http://www.indopedia.org/Tom_Van_Flandern.html
One Brow said: "One thing I read up on is the claim that if the speed of gravity propagation is c, the Earth's orbit would be unstable. This was not true, the speed being c is actually very compatible with stable orbits."
Did you even read Van Flandern's peer-reviewed (yet crankish, according to you) article on this topic? He clearly acknowledged that a faster-than-light-speed would violate SR, which it would. He did not say, however, that GR could not account for it, he just questioned whether that was the best physical interpretation:
"General relativity (GR) explains these features by suggesting that gravitation (unlike electromagnetic forces) is a pure geometric effect of curved space-time, not a force of nature that propagates...Problems with the causality principle also exist for GR in this connection, such as explaining how the external fields between binary black holes manage to continually update without benefit of communication with the masses hidden behind event horizons. These causality problems would be solved without any change to the mathematical formalism of GR, but only to its interpretation, if gravity is once again taken to be a propagating force of nature in flat space-time with the propagation speed indicated by observational evidence and experiments: not less than 2x1010 c. Such a change of perspective requires no change in the assumed character of gravitational radiation or its lightspeed propagation. Although faster-than-light force propagation speeds do violate Einstein special relativity (SR), they are in accord with Lorentzian relativity, which has never been experimentally distinguished from SR—at least, not in favor of SR."
His view may be right or wrong, and others may agree or disagree with his conclusions, but that alone hardly makes his criticisms, re causality, "invalid."
One Brow said: "You turn. Which of Van Flandern's criticisms do you think are valid?"
A few excerpts from wiki:
"Lorentz ether theory: This theory gives the same predictions in any experimental setting as special relativity. However, the two theories are ontologically and philosophically very different. As a result, they suggest different ways to extend or modify the theory (e.g., ways of understanding gravity)."
http://en.wikipedia.org/wiki/Status_of_special_relativity#Alternatives_to_special_relativity
"...Lorentz's theory became] both empirically and deductively equivalent to special relativity. The only difference was the metaphysical postulate of a unique absolute rest frame, which was empirically undetectable and played no role in the physical predictions of the theory....
Subsequent to the advent of special relativity, only a small number of individuals have advocated the Lorentzian approach to physics. Many of these, such as Herbert E. Ives (who, along with G. R. Stilwell, performed the first experimental confirmation of time dilation) have been motivated by the belief that special relativity is logically inconsistent, and so some other conceptual framework is needed to reconcile the relativitic phenomena....
"A few physicists, while recognizing the logical consistency of special relativity, have nevertheless argued in favor of the absolutist neo-Lorentzian view. Some (like John Stewart Bell) have asserted that the metaphysical postulate of an undetectable absolute rest frame has pedagogical advantages [B 27], while others have suggested that a neo-Lorentzian interpretation would be preferable in the event that any evidence of a failure of Lorentz invariance were ever detected."
http://en.wikipedia.org/wiki/Lorentz_ether_theory
With that background, Van Flandern explicitly does NOT claim that SR is logically inconsistent. His criticism is on metaphysical/ontological grounds, and on percieved it's violations of notions of causality. Right or wrong, these are certainly "valid criticisms," in my book. You may think that a critcism has to have been proven to be absolutely and unquestionably true, and to have utterly disproved SR in order to be "valid," though, eh?
One Brow asked: "If the first complaint is accompanied of by a picture of Obama bowing, ane the second by picture of some people being detained?"
Well, to begin with, that's not even equal proof for the two claims. The picture of Obama bowing (assuming it's not fake or out of context, e.g., doesn't show who he is bowing to) in and of itself proves the claim made.
But the very question still seems to be confusing the question of persuasion with sufficient evidence. If someone just doesn't "want" to believe something, no amount of evidence is sufficient. On the other hand, one can quite reasonably accept something as true or convincing, without demanding "sufficient proof" in every single case.
But, either way, sufficient proof should be sufficient proof. The standard would have to be something along the lines of what a reasonable man would take as sufficient proof of something he had no prior inclination to either believe or disbelieve. Again, we're talking about what "should" be done, not what every individual would in fact do.
My subjective needs, wishes, desires and/or fears should not be part of that. Suppose, for example, that I claim that I am willing to make an even-odds bet on anything that I am convinced is at least 60/40 in my favor. If that's true, the standard of proof should be no different whether I'm betting $1 or $1,000.
Suppose you say Deron is bigger than Christina and I respond: "Right! Christina is smaller than Deron, sho nuff!"
Would your response be: Wrong! Deron is bigger than Christina, not the other way around.
It may be more "conventional" and more "popluar" to phrase the relative difference the way you did, who knows? But that would not make one formulation right and the other wrong. They are both still equally valid.
As I understand it, GR itself has two equally viable physical interpretations: 1. a "field" interpretation and 2. a "geometrical" interpretation. Neither view is inconsistent with the underlying mathematics, and neither one is "more correct" than the other. Yet when I tell you that Einstein and others preferred the first view, your response implies that they are "wrong" by holding that view. Absent other distinguishing factors, this simply is not a matter of "right" and "wrong." But you treat it as such, because for you there is right opinion (aka popular opinion) and wrong opinion (unpopular, non-pc, opinion). If the popular thing to say is that "Deron is bigger than Christina," then, for you that is, and can only be, the "right" way to phrase the statement.
Likewise with SR vs. LR. For you, only the popular choice can be the "right" choice, it seems, and if you don't make the "right" choice, then obviously you have made the "wrong" choice. What is popular and conventional is right. What is unpopular and unconventional is wrong, based on those two considerations alone. Anyone with the "wrong" opinion is, ipso facto, a crank, a denialist, etc.
That's what the whole pc mentality is about: enforcing the acceptance of "right opinion." Of course, to hear them tell it, it aint about opinion, it is about "truth" vs. "falsity." Such is the lack of objectivity amongst that crew, I'm afraid.
I quoted wiki as saying: "A few physicists, while recognizing the logical consistency of special relativity, have nevertheless argued in favor of the absolutist neo-Lorentzian view. Some (like John Stewart Bell) have asserted that the metaphysical postulate of an undetectable absolute rest frame has pedagogical advantages."
What is Bell (of Bell's theorem reknown) even saying, ya think? Well, in part this, it seems:
One of Bell’s professed aims in his 1976 paper on ‘How to teach relativity’ was to fend off “premature philosophizing about space and time”19. He hoped to achieve this by demonstrating with an appropriate model that a moving rod
contracts, and a moving clock dilates, because of how it is made up and not because of the nature of its spatiotemporal environment."
http://philsci-archive.pitt.edu/archive/00000987/00/Michelson.pdf
As I understand it, Bell thought that students tended to take an absolutist view about the "truth" of scientific claims, which is erronoeous, and had a tendency to draw conclusions based on pre-conceptions.
The "popular is right" approach strives to do just the opposite. It attempts to inculcate "premature philosophizing about time and space," and to create a rigid preconception about what is "right" in this area of philosophy. Your previous pedantic discourse about what space "really" is displays this defect, I'm afraid.
Reading a little on Bell, it seems he too has "causality" reasons for preferring LR:
"But since the locality condition is strongly motivated by Special Relativity, Bell's Theorem and the associated experiments suggest, as Bell himself put it, an "apparently essential conflict between any sharp formulation [of quantum theory] and fundamental relativity. That is to say, we have an apparent incompatibility, at the deepest level, between the two fundamental pillars of contemporary theory...I would say that the cheapest resolution is something like going back to relativity as it was before Einstein, when people like Lorentz and Poincare thought that there was an aether -- a preferred frame of reference -- but that our measuring instruments were distorted by motion in such a way that we could not detect motion through the aether."
http://en.wikipedia.org/wiki/User:Tnorsen/Sandbox/Bell's_Theorem#Abandon_Fundamental_Relativity
This same article offers some of Bell's observations about the notion of "context" which we have discussed in this thread:
"In particular, learning about Bohm's theory helped Bell realize that the various "no hidden variables" theorems (of von Neumann and others), which had been taken almost universally by physicists as conclusively establishing something like the Copenhagen formulation of quantum theory, were all bogus....The 1966 paper shows that the "no hidden variables" theorems of von Neumann and others all made an unwarranted and unacknowledged assumption, which today is usually called "non-contextuality". The existence of Bohm's theory (in light of the alleged "impossibility proofs") could thus be understood on the grounds that it violated this assumption, i.e., manifested the relevant sort of "contextuality"."
Why did Bell like Bohm's theory? Well, same reason, it saves causality, even if it does raised serious questions about the validity of SR:
"Bell wrote: "Bohm's 1952 papers on quantum mechanics were for me a revelation. The elimination of indeterminism was very striking. But more important, it seemed to me, was the elimination of any need for a vague division of the world into `system' on the one hand, and `apparatus' or `observer' on the other....Even now the de Broglie - Bohm picture is generally ignored, and not taught to students. I think this is a great loss. For that picture exercises the mind in a very salutary way. The de Broglie - Bohm picture disposes of the necessity to divide the world somehow into system and apparatus. But another problem is brought into focus. This picture ... has a very surprising feature: the consequences of events at one place propagate to other places faster than light."
Given that you relied on Bell's theorem as exposing "reality," because, you said, it had been empirically verified, you may find it surprising that Bell says the implications it generates can be "resolved" by abandoning SR in favor on LR.
Of course it is also worth noting that: " Some physicists who have studied Bell's Theorem carefully point to alleged flaws or hidden assumptions in Bell's formulation of local causality and/or his derivation of (what Bell called) the Locality Inequality therefrom; such claims are controversial and will be addressed below."
Again, the question of what "empirically verifies" what is raised, as is the question of the accuracy of the premises underlying a hypothetical proposition. This are questions which I see you as routinely ignoring when deciding what counts as "real" and/or "true," Eric.
The reason I say this is not to be overly critical of you, it is to stimulate you to think about (and question) the actual basis for your conclusions and the assumptions they entail. Simply training yourself to recite the conclusions of "mainstream" science, without such analytical and critical scrutiny, may allow one to assume a posture of learning, knowledge, and understanding, but it does not lend credence to that posture.
One Brow said: One thing I read up on is the claim that if the speed of gravity propagation is c, the Earth's orbit would be unstable. This was not true, the speed being c is actually very compatible with stable orbits."
When you say this is "not true," then what does that imply about your definition of "truth." What makes a thing "not true?"
Carlip concedes that a gravitation speed of c would indeed create unstable orbits IF the effects of that are not otherwise exactly "offset" somehow. He further concedes that, while there are theoretical methods by which to create such offsets, the issue has not been solved experimentally, and that a greater-than-light speed is one way to resolve the question (the question being: "How is it possible to have stable orbits?").
Is your standard this: As long as some (unproven) alternate (i.e., alternate to a faster-than-light speed of gravity, in this case) explanation can be given for result X (stability of orbits, in this case) then ANY explanation of the stability must be "untrue?" If so, that would include the alternative explanation itself, right?
Is it therefore simply your position that nothing is true (given that some alternative explanation can always be given). Is that what you are trying to say? Or are you claiming that one of the two alternative explanations is "true," and the other "not true?"
The notion that SR "predicts" something fundamental about space or time is misleading if you think it has something to do with "observed facts." It merely dictates how observed facts are to be interpreted, by postulate.
Bell made this point: "The approach of Einstein differs from that of Lorentz in two major ways. There is a difference of philosophy, and a difference of style...The difference of style is that instead of inferring the experience of moving observers from known and conjectured laws of physics, Einstein starts from the hypothesis that the laws will look the same to all observers in uniform motion."
SR does even attempt to explain experience on the basis of known laws. It merely postulates what it will be. The SR notions of space and time merely follow from that postulate. The postulate does not follow from the observed facts.
Edit: "SR does NOT even attempt to explain experience on the basis of known laws." This is not a "crankish" view, sorry.
It's all pretty simple, actually. Einstein merely says "Why waste time trying to explain or prove what experience will be, and/or trying to explain "why" it should be that way. Let's just assume it all. Tell me that aint a lot easier, eh? Whaddaya say!?
Kinda like what guys like Plato, Hegel, and the whole lot of metaphysical philosophers done. Kinda like what Euclid and all them math guys done, ya know?
For me, the relativistic "solutions" to the twin paradox are bogus. They are bogus because no "solution" is needed, the whole problem presupposes abolute motion, as does the "solution."
Leaving that aside, what's the deal here?
1. In SR, although each twin will see the other as aging less slowly and as being younger, in "truth" the "stay-at-home" twin is right in his perceptions (his brother actually is younger) and the travelling twin is wrong in his perceptions (his brother is older, not younger).
Why is one "really" younger? Because the "time" is shorter for the travelling twin. In Einstein's words: "For the moving organism the lengthy time of the journey was a mere instant, provided the motion took place with approximately the speed of light." http://en.wikipedia.org/wiki/Twin_paradox
2. In LR it is the same result, with a different explanation. Yes, the travelling twin will be younger, and the stay-at-home will be older. Furthermore, both will expect this and neither will be deceived by his perceptions.
Why? Not because time is slower for one and faster for the other; time itself doesn't change. What does change is the rate at which natural regular phenonmena such at atomic vibrations, heartbeats, pulse, etc. with varying speed. Although the clocks on the moving ship slow down, time doesn't.
Which one makes more sense? The results are identical, so one is the "equivalent" of the other in terms of results. But which explanation makes more sense? Does time itself "really" change, or just appear to in the sense that the clocks run slow?
Note that even Einstein presupposes absolute motion when he refers to the "moving organism," which he is contrasting with one who has been "at rest." He's assuming one is "really" moving and one isn't (relative to each other, of course).
Van Flandern, and others who question SR, do not question the accuracy of it's mathematical formulas, claim "logical" inconsistencies, or claim the conclusions are wrong, They question the physical interpretation given, i.e., that time itself "really" changes).
Edit: "What does change is the rate at which natural regular phenonmena such at atomic vibrations, heartbeats, pulse, etc. OCCUR with varying speed."
The apparent paradox arises because the SR advocates start equivocating and changing their definitions in mid-stream, that's all. They start by saying there is no "privileged" frame of reference. They end by saying, in effect, that stay-at-home (at rest) frame of reference is indeed "privileged," because it tells the true story while the traveller's frame of reference tells a "wrong" story.
Their "explanation" is to say that, in this case, the earth cannot be seen to be moving while the spaceship remains at rest? Why not? Because the traveller will experience inertial changes when he reverses course, while no such changes will be experienced by the earth-bound twin. This is just another was of saying that absolute motion can be detected (by inertial changes) and that the spaceship is the object that is "really" moving, not the earth.
Many physical processes "slow down" with temperature changes too (as with speed). From the LR standpoint, one merely says, "I see, what causes that." To be consistent the SR advocate should say: "Ya fool! Physical processes don't slow down, only time does. Time has simply stopped for people in suspended animation, that's all."
Edit. Meant to say: "The apparent paradox is "resolved" [not "arises"] because the SR advocates start equivocating and changing their definitions in mid-stream, that's all."
If the SR advocates remained consistent, a true paradox would indeed arise. Since each frame of reference is equally valid ("true") then, in fact, each twin is younger than the other. But, like I said, they end up by saying that only one frame of reference is true and valid, i.e., they betray their original premise, and this causes the paradox to "disappear."
I didn't say his "take" was misleading, which it is not, the best I can tell.
Perhaps I read too much into Van Flandern, but it certainly seemed to me he was saying scientists just ignored GR when planning the GPS system, when that does not seem to have been true.
I didn't say I would automatically take anyone who called Van Flandern (or anyone else for that matter) a crank their word. Had Carlip called him a crank, based on years of correspondence, that would carry a lot more weight than some who never even read his work, but just didn't like his conclusions, for example.
http://www.lunchwithgeorge.com/lwg_gravity.html
"OK, Tom, let's try this one more time. (After this, I quit.) "
"Let me suggest, Tom, that you don't know enough general relativity to make a claim of this sort."
These words suggest Carlip saw Van Flandern as not knowledgeable and difficult to teach. I don't know if he ever used "crank" explicitly.
Suspicion in one thing, outright accusation is another. No one can be sued for libel for mere suspicion, as far as I know.
I do tend so say things flatly, often more so than I believe them to be.
What do you mean by "worked as well?"
Led to equally productive results. You can't distinguish between SR and LR directly by experiment, but SR produced the mass-energy equivalence law (E=mc^2) and is foundational to GR, while the same concepts did not originate in LR and do not come from it, from what I can tell.
http://en.wikipedia.org/wiki/Lorentzian_relativity#The_shift_to_relativity
You still seem to think that SR has somehow been "proven" over LR.
I do? Well, to the extant one has been more useful than the other, I suppose. But just like string theory, if you can form an experiment where the results are different, then you can't support one over the other on that basis.
To suspect, let alone conclude, that someone someone with a perfectly reasonable and supportable conclusion is a "crank" is simply a way of trying to support your position by illegitimate methods.
Did Van Falndern have any of these perfectly reasonable and supportable conclusions that were not predicted by SR/GR?
Does an error make one a crank? I trust that, even assuming that Carlip thought Van Flandern made mistakes at times (which no doubt both did think of the other along the line), he showed him how and why he thought so. In other words, he would say "You're wrong there because (X, Y, and Z) and not simply "You're wrong there because you are a crank."
I don't recall ever saying someone was wrong because they were a crank (or a denialist, for that matter).
A "crank" whose article on the speed of gravity passed peer review, eh? I see. Did you even read it, I wonder, or just know it wasn't worth reading, due to the crank status of Van Flandern?
To which publication do you refer? YEC articles get peer-reviewed, after all.
He clearly acknowledged that a faster-than-light-speed would violate SR, which it would.
I don't recall claiming that, and I don't think it is true that faster-than-light gravity propagation violates SR.
"General relativity (GR) explains these features by suggesting that gravitation (unlike electromagnetic forces) is a pure geometric effect of curved space-time, not a force of nature that propagates
GR is currently interpreted as a force that propagates as well as a field.
These causality problems would be solved without any change to the mathematical formalism of GR, but only to its interpretation, if gravity is once again taken to be a propagating force of nature in flat space-time with the propagation speed indicated by observational evidence and experiments: not less than 2x1010 c.
AFAICT, all current observations are consistent with c.
With that background, Van Flandern explicitly does NOT claim that SR is logically inconsistent. His criticism is on metaphysical/ontological grounds, and on percieved it's violations of notions of causality.
From what you have quoted, his claims regarding causality are not true.
But, either way, sufficient proof should be sufficient proof. The standard would have to be something along the lines of what a reasonable man would take as sufficient proof of something he had no prior inclination to either believe or disbelieve. Again, we're talking about what "should" be done, not what every individual would in fact do.
One distinction between ordinary and extraordinary claims is that the ordinary claims are those you are more inclined to believe, because they resemble the world as it ordinarily appears.
My subjective needs, wishes, desires and/or fears should not be part of that. Suppose, for example, that I claim that I am willing to make an even-odds bet on anything that I am convinced is at least 60/40 in my favor. If that's true, the standard of proof should be no different whether I'm betting $1 or $1,000.
As long as one amount of money has no more meaning that the other (that is, risk aversion plays no part), sure.
As I understand it, GR itself has two equally viable physical interpretations: 1. a "field" interpretation and 2. a "geometrical" interpretation. Neither view is inconsistent with the underlying mathematics, and neither one is "more correct" than the other.
That they are identical under the mathematics is not a guarantee they are interchangeable.
Yet when I tell you that Einstein and others preferred the first view, your response implies that they are "wrong" by holding that view.
I really wonder how you can take such meanings from my words sometimes.
Again, the question of what "empirically verifies" what is raised, as is the question of the accuracy of the premises underlying a hypothetical proposition. This are questions which I see you as routinely ignoring when deciding what counts as "real" and/or "true," Eric.
I'm aware that's what you see.
The reason I say this is not to be overly critical of you, it is to stimulate you to think about (and question) the actual basis for your conclusions and the assumptions they entail.
That would require separating conclusions from various other expressions.
Simply training yourself to recite the conclusions of "mainstream" science, without such analytical and critical scrutiny, may allow one to assume a posture of learning, knowledge, and understanding, but it does not lend credence to that posture.
How about that.
One Brow said: One thing I read up on is the claim that if the speed of gravity propagation is c, the Earth's orbit would be unstable. This was not true, the speed being c is actually very compatible with stable orbits."
When you say this is "not true," then what does that imply about your definition of "truth." What makes a thing "not true?"
In this particular case, I explained why it was not true explicitly.
Carlip concedes that a gravitation speed of c would indeed create unstable orbits IF the effects of that are not otherwise exactly "offset" somehow.
Exactly. Since the effects are offset by gravitomagnetism (which seems to have been observed indirectly), Van Flandern's claim of necessary instability is not true.
Aberration in general relativity
The finite speed of gravitational interaction in general relativity may at first seem to lead to exactly the same sorts of problems with the aberration of gravity that Newton was originally concerned with. In general relativity, however, (similar to the field theories above), gravitomagnetism effects cancel out the effects of aberration.[clarification needed] As shown by Carlip, in the weak stationary field limit, the orbital results calculated by general relativity are the same as those of Newtonian gravity (with instantaneous action at a distance), despite the fact that the full theory gives a speed of gravity of c.[12] Although the calculations are considerably more complicated, one can show that general relativity does not suffer from aberration problems just as electromagnetic retarded Liénard–Wiechert potential theory does not. It is not very easy to construct a self-consistent gravity theory in which gravitational interaction propagates at a speed other than the speed of light, which complicates discussion of this possibility.[13]
http://en.wikipedia.org/wiki/Speed_of_gravity
He further concedes that, while there are theoretical methods by which to create such offsets, the issue has not been solved experimentally, and that a greater-than-light speed is one way to resolve the question (the question being: "How is it possible to have stable orbits?").
How does this make Van Flandern's necessary instability claim true? Is it you impression that if Van Falndern's physics might be possible, than any claim he makes regarding the instability of orbits under GR must be true?
Is your standard this: As long as some (unproven) alternate (i.e., alternate to a faster-than-light speed of gravity, in this case) explanation can be given for result X (stability of orbits, in this case) then ANY explanation of the stability must be "untrue?"
You really say some silly things sometimes. Where in my paraphrase of Van Flandern did I address competing theories in any way?
The notion that SR "predicts" something fundamental about space or time is misleading ...
The notion that any scientific theory predicts anything fundamental about anything would be misleading.
1. In SR, although each twin will see the other as aging less slowly and as being younger, in "truth" the "stay-at-home" twin is right in his perceptions (his brother actually is younger) and the travelling twin is wrong in his perceptions (his brother is older, not younger).
No, not really. It's not like the traveling twin sees their sibling suddenly age upon arrival.
Calculation of elapsed time from the Doppler diagram
The twin on the ship sees low frequency (red) images for 2.57 years. During that time, he would see the Earth twin in the image grow older by 2.57/3.73 = 0.69 years. He then sees high frequency (blue) images for the remaining 2.57 years of his trip. During that time, he would see the Earth twin in the image grow older by 2.57×3.73 = 9.59 years. When the journey is finished, the image of the Earth twin has aged by 0.69 + 9.59 = 10.28 years.
The Earth twin sees 9.59 years of slow (red) images of the ship twin, during which the ship twin ages (in the image) by 9.58/3.73 = 2.57 years. He then sees fast (blue) images for the remaining 0.69 years until the ship returns. In the fast images, the ship twin ages by 0.69×3.73 = 2.57 years. The total aging of the ship twin in the images received by Earth is 2.57+2.57 = 5.14 years, so the ship twin returns younger (5.14 years as opposed to 10.28 years on Earth).
Why? Not because time is slower for one and faster for the other; time itself doesn't change. What does change is the rate at which natural regular phenonmena such at atomic vibrations, heartbeats, pulse, etc. occur with varying speed. Although the clocks on the moving ship slow down, time doesn't.
Which one makes more sense? The results are identical, so one is the "equivalent" of the other in terms of results. But which explanation makes more sense? Does time itself "really" change, or just appear to in the sense that the clocks run slow?
Given that choice, time slowing down seems much more intuitive than something that affects the clock's mechanisms but has no detectable mechanical effect.
Note that even Einstein presupposes absolute motion when he refers to the "moving organism," which he is contrasting with one who has been "at rest." He's assuming one is "really" moving and one isn't (relative to each other, of course).
Actually, I believe that would be relative to the inital, shared inertial state, not some absolute state.
They end by saying, in effect, that stay-at-home (at rest) frame of reference is indeed "privileged," because it tells the true story while the traveller's frame of reference tells a "wrong" story.
Not in what I've read.
If the SR advocates remained consistent, a true paradox would indeed arise.
This is false.
One Brow said: "Led to equally productive results. You can't distinguish between SR and LR directly by experiment, but SR produced the mass-energy equivalence law (E=mc^2) and is foundational to GR, while the same concepts did not originate in LR and do not come from it, from what I can tell."
This appears to be a widely held misconceptions. I have read that E = 3/4 MC2 was formulated in 1882 (the 3/4 accounted for by ether, or something) and that, at any rate, the formula is derived completely independently of SR.
One Brow said: "GR is currently interpreted as a force that propagates as well as a field."
I have no idea what you really mean here. GR is not a force under any account I've ever heard. If you mean GR's view of gravity, then that depends on your interpretation (whether field or geometrical view). Carlip says the field view is no longer "popular."
"Yet when I tell you that Einstein and others preferred the first view, your response implies that they are "wrong" by holding that view."
One Brow said: "I really wonder how you can take such meanings from my words sometimes."
I mentioned that Einstien, Dirac, and Feynman, among others, preferred the field view which Carlip said is "no longer popular." Your "response" was that just because Einstein was recent doesn't mean he can't be wrong. What did you mean, exactly?
One Brow said: "In this particular case, I explained why it was not true explicitly."
I missed it. Can you explain it again? Is your claim that the SR/GR view is "true" and that therefore any other view is "not true?"
One Brow said: "Exactly. Since the effects are offset by gravitomagnetism (which seems to have been observed indirectly), Van Flandern's claim of necessary instability is not true."
Nobody claims that that orbits are "necessarily unstable." We all know that stable orbits exist, even "cranks" like me and Van Flandern. You do seem to have a definite fondness for strawman arguments. Once again I have to ask: Did you even read his article? Did you even read the excerpts I posted?
One Brow said: "How does this make Van Flandern's necessary instability claim true? Is it you impression that if Van Falndern's physics might be possible, than any claim he makes regarding the instability of orbits under GR must be true?"
Van Flandern does NOT claim that orbits are unstable under GR, and I quoted his statement on this more than once. Just read it, eh? All these strawman around makes me nervous that an uncontrollable fire might break out, ya know?
One Brow said: "You really say some silly things sometimes. Where in my paraphrase of Van Flandern did I address competing theories in any way?"
I didn't "say" anything, I merely asked a question pertaining to your definition of truth? Care to answer it?
One Brow said: "No, not really. It's not like the traveling twin sees their sibling suddenly age upon arrival."
What do you mean, "no, not really?" What does the time at which the travelling twin sees his as having aged more rapidly even have to do with it? The statement you directed the "no, not really" response to was this:
"1. In SR, although each twin will see the other as aging less slowly and as being younger, in "truth" the "stay-at-home" twin is right in his perceptions (his brother actually is younger) and the travelling twin is wrong in his perceptions (his brother is older, not younger)."
Of course the real question here is not who sees what, when, but rather which perception is ultimately "correct" according to SR.
One Brow said: "Given that choice, time slowing down seems much more intuitive than something that affects the clock's mechanisms but has no detectable mechanical effect."
Heh, you are a deductive metaphysician to the core, Eric. You are also quite selective, it seems. What is the "mechanical" effect of "centripedal force," which GR relies heavily on, I wonder. (Don't bother answering, just think about it).
Perhaps you can explain the basis of your "intution" that time itself actually slows down, eh? Is that what you also "intuitively" think when physical processes slow down with temperature decreases?
You might also explain what this is even supposedly to mean, because it's not at all clear to me: "...something that affects the clock's mechanisms but has no detectable mechanical effect."
If "something" affects the clocks mechanisms, isn't that a "detectable mechanical effect?"
One Brow said: "Actually, I believe that would be relative to the inital, shared inertial state, not some absolute state."
Yeah, that's exactly what I said: "He's assuming one is "really" moving and one isn't (relative to each other, of course)." See the part in parentheses, there?
They end by saying, in effect, that stay-at-home (at rest) frame of reference is indeed "privileged," because it tells the true story while the traveller's frame of reference tells a "wrong" story.
One Brow said: "Not in what I've read." What have you read?
====
If the SR advocates remained consistent, a true paradox would indeed arise.
One Brow said: "This is false." Care you say why? I explained exactly why I think it is true. What part of that do you disagree with?
I said: "If that's true, the standard of proof should be no different whether I'm betting $1 or $1,000.
One Brow said: As long as one amount of money has no more meaning that the other (that is, risk aversion plays no part), sure.
Again, my point is simply that subjective persuasion/conviction is not a reasonable requirement for a standard of proof.
If someone gave me sufficient evidence that the odds of a certain thing happening are 60/40, then that is "sufficient evidence," irrespective of the amount I am willing to bet. I am of course free to say: "I aint bettin no $1000 unless it is at least 70/30 in my favor." But that has nuthin to do with "sufficient evidence" for a 60/40 probability.
One Brow said: "No, not really. It's not like the traveling twin sees their sibling suddenly age upon arrival."
This article warns one not to confuse what one sees with what might "calculate" in order to try to reconcile what he "sees" with what really "is:"
1. "That is, both twins would see the images of their sibling aging at a rate only 0.268 times their own rate, or expressed the other way, they would both measure their own aging rate as being 3.732 that of their twin. In other words, each twin will see that for each hour that passes for them, their twin experiences just over 16 minutes."
2. "To avoid confusion, note the distinction between what each twin sees, and what each would calculate."
This article specifically warns that one should not confuse what he twin actually "sees" with the "calculations" he would make to reconcile the discrepancies between what he sees and what "is:"
1. "To avoid confusion, note the distinction between what each twin sees, and what each would calculate."
2. "both twins would see the images of their sibling aging at a rate only 0.268 times their own rate, or expressed the other way, they would both measure their own aging rate as being 3.732 that of their twin. In other words, each twin will see that for each hour that passes for them, their twin experiences just over 16 minutes."
Note also that even the "doppler calculation" analysis presupposes that one twin is "really" moving and one isn't.
Here's another supposed "solution" to the paradox:
"He really does perceive only 6.4 years to pass on earth. But we have forgotten to take into account the desynchronization effect. Initially, the two clocks (biological in this case) are in sync with one another. But during his acceleration the clocks on board his ship go wildly out of sync with those on earth — 3.6 years out of sync to be precise."
http://physics123.net/2009/02/the-twin-paradox-explained/ This "explanation" claims that a 3.6 year difference will occur in one day (the day it is hypothesized that it take him to change directions). It still doesn't change what he sees (versus what he might calculate) and it still presupposes that only one twin is "really" moving. But you tried to make a point about "when" the changes are seen, this is relevant to that question.
The foregoing explanation is one addressed by Van Flandern and addresses what he calls "time slippage."
"In SR, the answer is not so simple; yet an explanation exists. The reciprocity of frames required by SR when Einstein assumed that all inertial frames were equivalent introduces a second effect on "time" in nature that is not reflected in clock rates alone. We might call this effect "time slippage" so we can discuss it. Time slippage represents the difference in time for any remote event as judged by observers (even momentarily coincident ones) in different inertial frames....
If the traveler orbits Alpha Centauri at a speed of 0.99 c, then whenever he is headed in the direction of Earth his opinion changes to Earth time "now" is 9/2002. And whenever he is again headed away from Earth, Earth time is once again 9/1994. Earth time "now" changes continually, according to SR, because of these time slippage effects needed to retain frame reciprocity. Earth residents -- even the ones who died in 1998 -- are oblivious to their repeated passages into the future and past of the traveling twin, with concomitant deaths and resurrections.
So when the traveler finally does return, he will indeed find that time on Earth is 10/2002, just as his GPS clock shows. He accounts for this as two months of elapsed time on Earth's slow-running clocks during his own 14-month (by his natural clock) journey, plus 8 years of "time slippage" when the traveler changed frames. There is no logical or mathematical inconsistency in this resolution, which is why SR remains a viable theory today."
http://www.metaresearch.org/cosmology/gps-relativity.asp
Heh, I like this part, ya know?: "Earth residents -- even the ones who died in 1998 -- are oblivious to their repeated passages into the future and past of the traveling twin, with concomitant deaths and resurrections."
To excerpt just a little more of Van Flandern's commentary (which I should have added before):
"There is no logical or mathematical inconsistency in this resolution, which is why SR remains a viable theory today. We are, of course, free to question whether or not this mathematical theory retains a valid basis under the principles of causality. For those of us who answer "yes", LR is unnecessary, and inelegant because it depends on a preferred frame. For those of us who answer "no", LR is then the better descriptor of nature, requiring the sacrifice of symmetry (“covariance”) to retain causality."
This is what I meant when I said: " Van Flandern explicitly does NOT claim that SR is logically inconsistent. His criticism is on metaphysical/ontological grounds, and on it's percieved violations of notions of causality. Right or wrong, these are certainly "valid criticisms," in my book."
One Brow said: "Given that choice, time slowing down seems much more intuitive than something that affects the clock's mechanisms but has no detectable mechanical effect."
Perhaps you could expound upon the "mechanical effect" that warped space and time dilation impose on material objects, eh? Keep in mind Bell's position that:
"He hoped to achieve this [i.e., premature philosophizing about time and space] by demonstrating with an appropriate model that a moving rod contracts, and He hoped to achieve this by demonstrating with an appropriate model that a moving rod contracts, and a moving clock dilates, because of how it is made up and not He hoped to achieve this by demonstrating with an appropriate model that a moving rod contracts, and a moving clock dilates, because of how it is made up and not because of the nature of its spatiotemporal environment."
In other words, can you show why (intuitively, or otherwise) a moving clock dilates "because of the nature of its spatiotemporal environment?"
This appears to be a widely held misconceptions. I have read that E = 3/4 MC2 was formulated in 1882 (the 3/4 accounted for by ether, or something) and that, at any rate, the formula is derived completely independently of SR.
HIstorically and pedagogically, mass-energy equivalence was a result of SR. I am sure there are ways to derive it outside of SR, but it follows from SR deductively.
I mentioned that Einstien, Dirac, and Feynman, among others, preferred the field view ...
I must have misunderstood, then. I thought you meant Einstein, Dirac, and Feynman all preferred a notion of quantum machanics that was deterministic due to local hidden variables, which by all accounts has been essentially disproven.
I missed it. Can you explain it again? Is your claim that the SR/GR view is "true" and that therefore any other view is "not true?"
My claim is that Van Flandern was wrong to say that GR predicts unstable orbits, and this claim is false.
Nobody claims that that orbits are "necessarily unstable." We all know that stable orbits exist, even "cranks" like me and Van Flandern. You do seem to have a definite fondness for strawman arguments. Once again I have to ask: Did you even read his article? Did you even read the excerpts I posted?
Do you think Van Flandern might have written a thing or two you have not posted? Perhaps:
If gravity from the Sun propagated outward at the speed of light, the transmission delay would progressively increase the angular momentum of bodies orbiting the Sun at so great a rate that orbital radii would double in about 1000 revolutions.
http://ldolphin.org/vanFlandern/
Van Flandern does NOT claim that orbits are unstable under GR, and I quoted his statement on this more than once.
Your presumption that you have presented the full extant of his claims is characteric of many of the attributes you constantly try to lay upon me.
I didn't "say" anything, I merely asked a question pertaining to your definition of truth? Care to answer it?
I have answered it many times, and I think I answered it last time. That you read past it, I can not explain. If you care to rephrase, I'll try to do likewise.
Edit: Lot of unintentional repetition in that last post. Just is case you can't make sense of it, it should have read:
"He hoped to achieve this [i.e., premature philosophizing about time and space] by demonstrating with an appropriate model that a moving rod contracts, and a moving clock dilates, because of how it is made up and not because of the nature of its spatiotemporal environment."
In other words, can you show why (intuitively, or otherwise) a moving clock dilates "because of the nature of its spatiotemporal environment?"
One Brow said: "No, not really. It's not like the traveling twin sees their sibling suddenly age upon arrival."
What do you mean, "no, not really?" What does the time at which the travelling twin sees his as having aged more rapidly even have to do with it? The statement you directed the "no, not really" response to was this:
"1. In SR, although each twin will see the other as aging less slowly and as being younger, in "truth" the "stay-at-home" twin is right in his perceptions (his brother actually is younger) and the travelling twin is wrong in his perceptions (his brother is older, not younger)."
Of course the real question here is not who sees what, when, but rather which perception is ultimately "correct" according to SR.
Each twin is correct in his perceptions. I think you are assuming that the notion of "simoultaneous" can apply to objects in different locations, and that is why the paradox is giving you trouble.
Heh, you are a deductive metaphysician to the core, Eric. You are also quite selective, it seems. What is the "mechanical" effect of "centripedal force," which GR relies heavily on, I wonder. (Don't bother answering, just think about it).
Motion in a given direction (toward a mass) is a mechanical effect.
What is the mechanical effect in LR that slows any different type of clock down by the same amount? Whether they measure mechanically, by electricity, or by the change in electrical orbits (atomic clocks), each is effected in the exact same way. Whether the ruler is made from wood, metal, plastic, or diamond, it shrinks the same amount.
Perhaps you can explain the basis of your "intution" that time itself actually slows down, eh?
It's only one odd effect, instead of multiple odd effects on different systems which are exactly the same.
Is that what you also "intuitively" think when physical processes slow down with temperature decreases?
I would teh prefer zero odd effects over one.
If "something" affects the clocks mechanisms, isn't that a "detectable mechanical effect?"
It dosn't change the energy stored in the spring of a wind-up clock, or the voltage of a battery, etc. Why the clock moves more slowly would be have to be different for different clocks.
Yeah, that's exactly what I said: "He's assuming one is "really" moving and one isn't (relative to each other, of course)." See the part in parentheses, there?
Not relative to each other, relative to the initial inertial state they first shared.
What have you read?
Sorry, I should have included the link:
http://en.wikipedia.org/wiki/Twin_paradox
Note that you can calculate the time passed for the inertial twin from the point of view of the accelerted twin, and it will show the inertial twin ages faster.
But that has nuthin to do with "sufficient evidence" for a 60/40 probability.
I don't think this is relevant to the standard of extradinary evidence for extraordinary claims, since it would take more evidence to reach 60/40 for the former.
2. "To avoid confusion, note the distinction between what each twin sees, and what each would calculate."
Due to the doppler effect, the second twin sees very rapid aging on the return journey to the inertial frame.
Note also that even the "doppler calculation" analysis presupposes that one twin is "really" moving and one isn't.
What does "really moving" mean, here? Is intertial movement somehow unreal movement?
The foregoing explanation is one addressed by Van Flandern and addresses what he calls "time slippage."
It's really didn't make much sense to me. It does not resemble the description in the wiki article at all.
In other words, can you show why (intuitively, or otherwise) a moving clock dilates "because of the nature of its spatiotemporal environment?"
As best I can parse this, my answer is: the clock does not change at all in SR/GR.
His criticism is on metaphysical/ontological grounds, and on it's percieved violations of notions of causality. Right or wrong, these are certainly "valid criticisms," in my book."
Only if he demonstrtates genuine causal violations, and I do not agree he does that.
Perhaps you could expound upon the "mechanical effect" that warped space and time dilation impose on material objects, eh?
Not really, but at least it is a single effect, not multiple effects happening in parallel on very different items.
One Brow said: "Your presumption that you have presented the full extant of his claims is characteric of many of the attributes you constantly try to lay upon me."
I presented his full argument on this topic in question IN CONTEXT. I posted it verbatim, and you ignored it. You took one sentence out of context to try to support this manuever. Is what you quoted the "full extent of his claims," ya figure? I do not, and never have, claimed to have presented "the full extent of his claims" anywhere (he makes all kinda claims that I haven't even mentioned).
One Brow said: "What is the mechanical effect in LR that slows any different type of clock down by the same amount? Whether they measure mechanically, by electricity, or by the change in electrical orbits (atomic clocks), each is effected in the exact same way. Whether the ruler is made from wood, metal, plastic, or diamond, it shrinks the same amount."
There are various accounts for this, and some of which I have quoted in this thread, which I haven't memorized. Whatever J.S. Bell had in mind, for example.
Once again your presumption that what you don't know doesn't exist seems to raise it's head. Suppose I know that water freezes and becomes ice. Further suppose that I have no mechanical theory to explain it. Now what? Should I therefore conclude that water doesn't really freeze?
One Brow said: "Not relative to each other, relative to the initial inertial state they first shared."
This is a distinction without a difference. The initial inertial frame they first shared" is presumed to have been maintained throughout by the "stay-at-home." In other words it is the earth's inertial frame of reference, ya know?
One Brow said: "What does "really moving" mean, here? Is intertial movement somehow unreal movement?"
It means, in this case, that it is presumed that the traveller "actually" went out, turned around, and then came back," rather than vice versa.
One Brow said: "Due to the doppler effect, the second twin sees very rapid aging on the return journey to the inertial frame." That's not what the article said about what the twin "sees." Again, as it warned, you need to distinguish between what the twin sees from what he "calculates" with deliberation, meditation and and a slide rule in order to "make sense of" his deceptive and erroneous perception.
One Brow said: "It's really didn't make much sense to me. It does not resemble the description in the wiki article at all."
Although stated differently, this is the "solution" which I think the wiki article addresses under the heading "Resolution of the paradox in general relativity," the first sentence of which says: "The issue in the general relativity solution is how the traveling twin perceives the situation during the acceleration for the turn-around."
Note that in this "explanation" also, that "in modern interpretation it is only perceptual because it is caused by the traveling twin's acceleration."
So, here again, it is assumed that it is the travelling twin (not the earth) which is accelerating, which means that it is the traveller who is "really" moving away from the earth, rather than the earth moving away from him.
This same issue was addressed, in a summary fashion, in the first part of the wiki article, where it says:
"Starting with Paul Langevin in 1911, there have been numerous explanations of this paradox, all based upon there being no contradiction because there is no symmetry — only one twin has undergone acceleration and deceleration, thus differentiating the two cases... (skip ahead a little)
Langevin explained the different aging rates as follows: “Only the traveler has undergone an acceleration that changed the direction of his velocity”. According to Langevin, acceleration is here "absolute"...."
There is "no symmetry" because Einstein's postulate is being ignored, and because the "solution" implicitly assumes an absolute motion between the two--the earth remains stationary and the rocket "moves," also contrary to the "no preferred frame" dictum. Absolute motion, detectable by virtue of inertial forces caused by "acceleration," is the underlying premise.
One Brow said: "As best I can parse this, my answer is: the clock does not change at all in SR/GR."
So you're sayin that the clock does not "slow down" relative to an object moving at a lesser speed? Would you then assert, as you wrongly accused Van Flandern of doing, that no "adjustments" are needed?
Perhaps you can explain the basis of your "intution" that time itself actually slows down, eh?
One Brow said: It's only one odd effect, instead of multiple odd effects on different systems which are exactly the same.
Sure, you can reduce the number of effects to be explained by positing reality, and then refusing to consider why such a posulation is reasonable or is supposed to "make sense." From there, you can just "deduce" all reality. Bell on the topic, once again:
"...Einstein starts from the HYPOTHESIS that the laws will look the same to all observers in uniform motion. This permits a very precise and elegant formulation on the theory, as often happens when one big assumption can be made to cover several less big ones."
http://books.google.com/books?id=FGnnHxh2YtQC&dq=speakable+and+unspeakable+in+quantum+mechanics&printsec=frontcover&source=bn&hl=en&ei=1U8LS63yDo6INs_36coC&sa=X&oi=book_result&ct=result&resnum=5&ved=0CCgQ6AEwBA#v=onepage&q=&f=false
Given that this is your primary criterion of truth, I would expect you to be an outspoken advocate for the "truth" of string theory and Plato's theory of forms, ya know?
One Brow said: Only if he demonstrtates genuine causal violations, and I do not agree he does that.
OK, you're free to agree or disagree as your whim or your expertise may lead you. Bell (who says one must abandon SR to save causality) and many others do not agree with you, but it's just a matter of philosophical preference as to whether "causality" is even important, I spoze.
I would just suggest that you not mistake your ontological preferences for "scientific truth," ya know?
One Brow said: It's only one odd effect, instead of multiple odd effects on different systems which are exactly the same.
It's kinda odd that absolute zero is thought to affect all things, too, aint it? Better to simply say that time does it, because at temperatures of absolute zero time stops. That would explain it all, elegantly.
Talkin bout string theory, and all, them guys seem to like particles that travel faster than light, ya know?
"A tachyon is a hypothetical subatomic particle that travels faster than the speed of light...
In string theory tachyons have the same interpretation as in quantum field theory. However, string theory can, at least in principle, not only describe the physics of tachyonic fields, but also predict whether such fields appear. Tachyonic fields indeed arise in many versions of string theory...
Despite the theoretical arguments against the existence of tachyon particles, experimental searches have been conducted to test the assumption against their existence; however, no experimental evidence for or against the existence of tachyon particles has been found."
http://en.wikipedia.org/wiki/Tachyon
What's up with string theorists, I wonder? Aint they even heard of SR?
One Brow said: "Not relative to each other, relative to the initial inertial state they first shared."
This is a distinction without a difference.
Actually, it makes a difference from both the point of view of the stationary twin, who is in one intertial reference frame, and from that of the traveling twin, who is in three or four different inertial reference frames.
The initial inertial frame they first shared" is presumed to have been maintained throughout by the "stay-at-home." In other words it is the earth's inertial frame of reference, ya know?
Exactly.
It means, in this case, that it is presumed that the traveller "actually" went out, turned around, and then came back," rather than vice versa.
So, you meant changed inertial environments. OK.
One Brow said: "Due to the doppler effect, the second twin sees very rapid aging on the return journey to the inertial frame."
That's not what the article said about what the twin "sees."
I suggest you re-read the first paragraph under "Calculation of elapsed time from the Doppler diagram". The shipboard twin sees his earth-bound counterpart age 9.59 years in what he experiences as 2.57 years.
Again, as it warned, you need to distinguish between what the twin sees from what he "calculates" with deliberation, meditation and and a slide rule in order to "make sense of" his deceptive and erroneous perception.
True, but the seen effects still reflect rapid aging on the return trip.
So, here again, it is assumed that it is the travelling twin (not the earth) which is accelerating, which means that it is the traveller who is "really" moving away from the earth, rather than the earth moving away from him.
Meanwhile, the wiki article specifically rules out acceleration per se as the explanation, and instead relies on the change of inertial reference frames..
This same issue was addressed, in a summary fashion, in the first part of the wiki article, where it says:
"Starting with Paul Langevin in 1911, there have been numerous explanations of this paradox, all based upon there being no contradiction because there is no symmetry — only one twin has undergone acceleration and deceleration, thus differentiating the two cases... (skip ahead a little)
Immediately below: "As shown by Max von Laue in 1913, the process of acceleration is not as important as Langevin suggested, because the asymmetric aging is completely accounted by the fact that the astronaut twin travels in two separate frames, while the earth twin remains in one frame. Using Minkowski's spacetime formalism, Laue went on to demonstrate that the world lines of the inertially moving bodies maximize the proper time elapsed between two events."
An interesting juxtaposition with your accusation of my taking a quote out of context.
There is "no symmetry" because Einstein's postulate is being ignored, and because the "solution" implicitly assumes an absolute motion between the two--the earth remains stationary and the rocket "moves," also contrary to the "no preferred frame" dictum. Absolute motion, detectable by virtue of inertial forces caused by "acceleration," is the underlying premise.
There is no symmetry because one observer has changed inertial frames and the other observer has not.
I presented his full argument on this topic in question IN CONTEXT. I posted it verbatim, and you ignored it.
When you ask me whether a person has made any invalid claims, I do not feel teh need to restrict myself solely to the portion of his beliefs you quote. Sorry if that is too much trouble for you.
took one sentence out of context to try to support this manuever.
It was the first line of the abstract Van Flandern wrote. It was there to *set* the context. Your pretense that I misrepresented him is laughable.
Here's another false claim:
According to SR, all these clock-reading inferences are not just illusions, but reflect the real, physical time for each frame involved. So at the same time and place that an AC resident infers that Earth time is 2004 February, the spacecraft traveler infers it is 2000 February - a four-year difference; and both are correct for their respective frames.
Then the spacecraft turns around. Nothing changes locally. But inferences about remote time change greatly because of time slippage, which now has the opposite sign. Now the traveler infers that Earth time is 2008 February - four years into the future instead of the past. As a consequence, the traveler will again infer that only one month of Earth time will elapse during the return journey, and all participants agree that Earth time upon the traveler's return will be 2008 March.
SR does not predict a "time slippage" or an instant adding of eight years when the ship turns around.
There are various accounts for this, and some of which I have quoted in this thread, which I haven't memorized. Whatever J.S. Bell had in mind, for example.
Outside of moving through ether, I don't recall a single mechanism you have posted. With regard to Bell, you posted that he noted their is a fundamental disagreement between SR/GR and quantum mechanics, but no mechanisms to explain the changes of LR.
Once again your presumption that what you don't know doesn't exist seems to raise it's head. Suppose I know that water freezes and becomes ice. Further suppose that I have no mechanical theory to explain it. Now what? Should I therefore conclude that water doesn't really freeze?
Water, vegetable oil, and carbon dioxide all freeze, but all at different temperatures. Lack of molecular energy affects different substances in different ways. Moving through ether affects everything in exactly the same way, according to LR.
One Brow said: "As best I can parse this, my answer is: the clock does not change at all in SR/GR."
So you're sayin that the clock does not "slow down" relative to an object moving at a lesser speed?
In LR, the clock slows down, but you can't detect it within that framework because every other clock has slowed down an identical amount, and your brain has been slowed down by the exact same amount. Every clock ticks one second when in the absolute reference frame, 1.2 or 2 or whatever have passed. In SR, the clock does not slow down. It seems slower to an observer in a different frame becasue time itself is slower.
Would you then assert, as you wrongly accused Van Flandern of doing, that no "adjustments" are needed?
No.
Sure, you can reduce the number of effects to be explained by positing reality, and then refusing to consider why such a posulation is reasonable or is supposed to "make sense." From there, you can just "deduce" all reality.
I suppose that is possible.
Given that this is your primary criterion of truth,
It is?
OK, you're free to agree or disagree as your whim or your expertise may lead you. Bell (who says one must abandon SR to save causality) and many others do not agree with you, but it's just a matter of philosophical preference as to whether "causality" is even important, I spoze.
I read Bell as saying a move from SR to LR *might* be able to integrate relativity with quantum mechanics, but causality does seem to be one of the issues.
I would just suggest that you not mistake your ontological preferences for "scientific truth," ya know?
I would suggest that the preference for fruitful ontological positions is a reasonable one to make.
It's kinda odd that absolute zero is thought to affect all things, too, aint it?
Absolute zero is not a mechanism, it is a description of a state which may not even be theoretically possible.
Better to simply say that time does it, because at temperatures of absolute zero time stops. That would explain it all, elegantly.
I suppose, although if time stops, than can something at absolute zero be heated? Can you have change without time? It seems unweildly. Stranger things have been evidenced, though.
What's up with string theorists, I wonder? Aint they even heard of SR?
SR is only the best explanation until it isn't.
One Brow said: "I suggest you re-read the first paragraph under "Calculation of elapsed time from the Doppler diagram". The shipboard twin sees his earth-bound counterpart age 9.59 years in what he experiences as 2.57 years."
I suggest that you read the article more closely and/or re-read what I've already pointed out to you from the article 2-3 times, eh? What he CALCULATES (which is what you are referring to here) is NOT what he SEES.
One Brow said: "An interesting juxtaposition with your accusation of my taking a quote out of context."
You're missing the whole point, Eric, and it is not unusual for you to look at two different words or phrasings and think that, because the two are different, the two must mean something entirely different.
Call it acceleration, or call it "two different frames," the point remains the same. It is always the traveller, not the earth which (take your pick) has two frames and/or acceleration. When they then analyze the situation from the earth's frame of reference, it is always a (take your pick) single frame of reference and/or stationary (not accelerating).
The point remains the same: "absolute" motion between the two is presupposed, the earth remains stationary while the rocket moves, and it is insisted that you CANNOT (as Einstein insisted you must) treat the two as equivalent, because one is "really" moving, and the other is "really" stationary.
Well, here is is again:
I said: "There is "no symmetry" because Einstein's postulate is being ignored, and because the "solution" implicitly assumes an absolute motion between the two"
You said: "There is no symmetry because one observer has changed inertial frames and the other observer has not."
In this context, the two statements are equivalent. The reason one has not changed intertial frames" is BECAUSE it is deemed to be stationary. The reason the one has is because he is the one moving, relative to the other, rather than vice versa.
The substance remains to the, however you choose to phrase it, to wit: ""Starting with Paul Langevin in 1911, there have been numerous explanations of this paradox, all based upon there being no contradiction because there is no symmetry — only one twin has undergone acceleration and deceleration, thus differentiating the two cases..."
Whether this wiki author realizes it, or not, this is substantially the same statement: "the asymmetric aging is completely accounted by the fact that the astronaut twin travels in two separate frames, while the earth twin remains in one frame."
The "acceleration" is what accounts for the two frames/one frame difference, too.
One Brow said: "When you ask me whether a person has made any invalid claims, I do not feel teh need to restrict myself solely to the portion of his beliefs you quote."
What!? We are talking about the same belief here, not a different one. You want to severely restrict the context, that's all.
If I said: "If I was a fool, I might think that Santa Claus really exists," you would probably want to "restict yourself" to: aintnuthin said, and I quote, "Santa Claus really exists."
One Brow said: "SR does not predict a "time slippage" or an instant adding of eight years when the ship turns around."
Van Flandern is talking about what a traveller "infers:" "inferences about remote time change greatly because of time slippage, which now has the opposite sign. Now the traveler infers that Earth time is 2008 February - four years into the future instead of the past."
The "inferences" serve to "explain" why he reaches the conclusions he does (which is not the same as what GR "predicts'). The time slippage is used to "explain" the observer's conclusions. Keep in mind that Van Flandern is using a "GPS clock," not a standard clock, in this illustration, which changes (and complicates) matters.
One Brow said: "With regard to Bell, you posted that he noted their is a fundamental disagreement between SR/GR and quantum mechanics, but no mechanisms to explain the changes of LR."
Really? Then what do you make of this: "He hoped to achieve this by demonstrating with an appropriate model that a moving rod contracts, and a moving clock dilates, because of how it is made up and not because of the nature of its spatiotemporal environment."
Remember, he was trying to "achieve" the avoidance of "premature philosophing." But what he was actually doing (to achieve the desired end) was demonstrating that an object changes "because of how it is made up and not because of the nature of its spatiotemporal environment."
One Brow said: "In LR, the clock slows down, but you can't detect it within that framework because every other clock has slowed down an identical amount, and your brain has been slowed down by the exact same amount. Every clock ticks one second when in the absolute reference frame, 1.2 or 2 or whatever have passed. In SR, the clock does not slow down. It seems slower to an observer in a different frame becasue time itself is slower."
So you have a new solution to the twin paradox, that it? Neither twin's clock actually "slows down," it only seems that way to each of the others, but it doesn't "really" happen, so they are in fact identical ages when the twin returns, eh?
Well, reading your post again, you're sayin that "time itself" is slower, so I guess that would make them age differently, eh?
And "time itself" is what, exactly? Is that something you can observe? It is something you can measure (without clocks)? Is it an "empirical" thing, or simply a concept?
Why is it, I wonder, that when scientists synchonrize two clocks, then send one off at a high rate of speed, the two clocks show different times when the travelling one returns? You said the clocks don't change, and don't "really" slow down, but isn't that claim contrary to what the scientific experiments have shown?
Do you even see the question? Suppose both clocks had the exact same time when one returns? Would that mean "time" didn't change when one was travelling? Or would it mean, as you seem to imply, that time agreement would be proof that only "time," not clocks, slowed down for the faster-moving clock?
I suggest that you read the article more closely and/or re-read what I've already pointed out to you from the article 2-3 times, eh? What he CALCULATES (which is what you are referring to here) is NOT what he SEES.
The Doppler effect refers to what happens to visible light traveling between bodies in different indertial reference frames. It is absolutely about what the ship-board twin sees. You can keep on trying to point things out, but until you understand this point, it will not be convincing.
The point remains the same: "absolute" motion between the two is presupposed, the earth remains stationary while the rocket moves, and it is insisted that you CANNOT (as Einstein insisted you must) treat the two as equivalent, because one is "really" moving, and the other is "really" stationary.
It's rather funny watching you try to interpret this. Einstein never insisted that a changing inertial reference frame must be treated as the same as an unchanging reference frame.
I said: "There is "no symmetry" because Einstein's postulate is being ignored, and because the "solution" implicitly assumes an absolute motion between the two"
You said: "There is no symmetry because one observer has changed inertial frames and the other observer has not."
In this context, the two statements are equivalent. The reason one has not changed intertial frames" is BECAUSE it is deemed to be stationary.
Stationary compared to what? Itself? What makes you think stationary is even meaningful in SR? Is there such a thing as a non-stationary inertial frame?
The reason the one has is because he is the one moving, relative to the other, rather than vice versa.
The twin paradox is unchanged if, from the viewpoint of earth, the twins are born on a plaentoid traveling .9c, and one gets into a ship that decelerates (from our point of view) to match earth's inertial reference frame, then re-accelerates to catch up to the planetoid. The shipboard twin will still be younger, because it is relative motion, not "absolute motion between the two", that causes the changes.
The "acceleration" is what accounts for the two frames/one frame difference, too.
The difference is that the acceleration is not used directly to calculate the varying time perceptions, only the velocities of the current references frames are (including an averaging of the velocity when under acceleration).
What!? We are talking about the same belief here, not a different one.
Van Flandern clearly believe that the speed of gravity being c leads to unstable orbits. He seems to believe in a 8-year jump that comes from turning the twin's ship, although I maight have misread that.
Van Flandern is talking about what a traveller "infers:" "inferences about remote time change greatly because of time slippage, which now has the opposite sign. Now the traveler infers that Earth time is 2008 February - four years into the future instead of the past."
Why would a shipboard traveller make this inference, when what he sees is not in agreement with it? What leads to this inference?
Really? Then what do you make of this: "He hoped to achieve this by demonstrating with an appropriate model that a moving rod contracts, and a moving clock dilates, because of how it is made up and not because of the nature of its spatiotemporal environment."
I infer that he never produced such a model, probably because he could not get a mechanism for it, unless you have some reason to change "hoped to achieve" into "acheived". I am not disputing his aspiration.
And "time itself" is what, exactly? Is that something you can observe?
I think that's a little beyond this discussion.
It is something you can measure (without clocks)?
Like measuring length without a ruler? It think that's what a clock is.
Is it an "empirical" thing, or simply a concept?
Am I a brain in a jar?
Why is it, I wonder, that when scientists synchonrize two clocks, then send one off at a high rate of speed, the two clocks show different times when the travelling one returns? You said the clocks don't change, and don't "really" slow down, but isn't that claim contrary to what the scientific experiments have shown?
The LR interpretation is that one clock slowed. The SR interpretation is that both clocks accurately tracked time locally, but the local times proceeded differently.
Do you even see the question? Suppose both clocks had the exact same time when one returns? Would that mean "time" didn't change when one was travelling?
That would be one interpretation.
Or would it mean, as you seem to imply, that time agreement would be proof that only "time," not clocks, slowed down for the faster-moving clock?
I don't see how time agreement implies this.
With respect to the twin question, I take you to be saying that even if one only "aged" 10 years and the other 50 years, they would still both "look" 50 years older. No one would know from looking at him and his brother that one had aged less (because time slowed down for him to the tune of 40 earth years) but it did not alter the "mechanical" aspect of his aging (grey hair, etc.)
One Brow said: "The Doppler effect refers to what happens to visible light traveling between bodies in different indertial reference frames. It is absolutely about what the ship-board twin sees. You can keep on trying to point things out, but until you understand this point, it will not be convincing."
Of course it's about what he sees, no one said it wasn't. The question is "what does he see (given the doppler effect)? According to the wiki article:
"Now, how would each twin observe the other during the trip? Or, if each twin always carried a clock indicating his age, what time would each see in the image of their distant twin and his clock? The solution to this observational problem can be found in the relativistic Doppler effect....That is, both twins would see the images of their sibling aging at a rate only 0.268 times their own rate, or expressed the other way, they would both measure their own aging rate as being 3.732 that of their twin. In other words, each twin will see that for each hour that passes for them, their twin experiences just over 16 minutes."
Is there something unclear about that to you?
The point is that what he calculates is NOT what he sees. Is there something unclear about that to you?
I said: "The point remains the same: "absolute" motion between the two is presupposed, the earth remains stationary while the rocket moves, and it is insisted that you CANNOT (as Einstein insisted you must) treat the two as equivalent, because one is "really" moving, and the other is "really" stationary.
One Brow responded: It's rather funny watching you try to interpret this. Einstein never insisted that a changing inertial reference frame must be treated as the same as an unchanging reference frame.
It's kinda funny watching you think you are responding to a statement which you evidently don't understand with a straw man non sequitur which misses the point, eh?
For the record, I never denied this, and never will: "Einstein never insisted that a changing inertial reference frame must be treated as the same as an unchanging reference frame."
What Einstein insisted was that the concept of absolute motion was "meaningless," that only relative motion could be detected, and that no one frame of reference could be preferred over another in an attempt to determine which one is "really" moving. You simply cannot say which object is moving, according to Einstien. Yet all these examples assume that one object is moving, and one isn't. It is only by doing so that you can say there is "asymmetry."
The point here is simple. After all the wordy explanations, the question becomes: So why can't we say the earth is moving and not the rocket? If we do that, which you say is permissible, then the very same analysis will reverse itself, and the earth twin will be younger, not the rocket-ship twin. Are both younger than the other?
The answer: Because the earth isn't the one moving, it hasn't accelerated. If it was the one moving, inertial effects would be noticeable. In that way, we are told that it is the rocket ship that is really moving, not the earth.
As a result, the perceptions of the earth-bound twin are given preference, because his perceptions are right, and his twin's are wrong.
I never said the acceleration "causes" any aging affects (although I do believe GR would claim otherwise). That's not the point. It causes the asymmetry.
Look at this another way: Two people are born at the same instant, at (virually) the same place. One is born on earth, the other on a ship travelling .99c 100 feet above him. Thereafter, each sees the other as being younger. Question: Who is really younger? Both? Neither? Meaningless question?
To finish off the observation/caculation distinction, the wiki articles says:
"As seen above, the ship twin can convert his received Doppler-shifted rate to a slower rate of the clock of the distant clock for both red and blue images. If he ignores simultaneity, he might say his twin was aging at the reduced rate throughout the journey and therefore should be younger than him. He is now back to square one, and has to take into account the change in his notion of simultaneity at the turn around. The rate he can calculate for the image (corrected for Doppler effect) is the rate of the Earth twin's clock at the moment it was sent, not at the moment it was received."
The rocket twin is forced to do conversions. "If he ignores simultaneity, he might say his twin was aging at the reduced rate throughout the journey and therefore should be younger than him. He is now back to square one, and has to take into account the change in his notion of simultaneity at the turn around."
Here again, the "turn-around" is crucial, and it is the ship, not the earth, which "turns around."
One Brow said: "I infer that he never produced such a model, probably because he could not get a mechanism for it, unless you have some reason to change "hoped to achieve" into "acheived". I am not disputing his aspiration."
Once again you demonstrate a couple of recurring tendencies, Eric:
1. What you don't know about doesn't exist, and
2. You don't seek to empirically verify the conclusions you deduce from your presuppositions. You don't have to. They are "necessarily" (in a tautological sense) true.
3. That, because you already know the answer, there is no real need to read my posts either.
How could he "demonstrate" something he didn't have, you ever ask yourself that? The web is filled with mechanical models which purport to show how and why objects do vary in length and frequency (time), if you care to look. Just because you have never bothered yourself to seek an explanation does NOT mean they don't exist.
You say: "unless you have some reason to change "hoped to achieve" into "acheived". The part I have quoted, at least twice, as well as the content of the post you are responding to, where I SPECIFICALLY brought this to you attention in the hope you wouldn't overlook it again (wishful thinkin), makes it clear that it was NOT referring to a "hope to achieve a model."
It was a hope to "achieve" a delay on premature philosophizing. To do this he USED a model (not tried to achieve one).
Or would it mean, as you seem to imply, that time agreement would be proof that only "time," not clocks, slowed down for the faster-moving clock?
One Brow said: I don't see how time agreement implies this.
If speed has "no effect" on a clock then two clocks would read the same whether they had been moving at the same speed or not. Of course the speed is only an "indirect" cause, but either way the clocks have changed. I understood your claim to be that only time, not clocks, would be affected by speed, because there are no mechanical changes to explain. "Slower time" explains it all.
I think I see what you are saying now, but only in the sense that I know what you are trying to say. It is incomprehensible to me that "time" (which clocks measure) changes the clock. Easy enough to say, but very hard to give any meaningful content to.
If I said "the spirit" changes matter, then you would naturally ask: "What is the spirit?" My answer would probably then be: "the spirit is the spirit, that's all you need to know." Don't ask me what it is, how it works, or anything like that. It just is what it is.
I look at "time" about the same way. It's easy for me to say "time," and easy to attribute all kinds of magical powers to it, as a independently existing "force," but very hard to give meaningful content to when viewed as such. It all sounds incomprehensibly mystical to me when presented in that way.
What you seem to be suggesting is that there is in fact an absolute, independently existing thing called "time," which clocks sense and respond to. It's like a clock somehow knows what a "real" second is (because time tells it) and changes its rate of mechanical operation to comply with the dictates of time (rather than to the springs, gears, etc. contained within it). If time slows, then the clock makes internal changes to slow it's own ticking rate because time has "told" it to.
And you think the many naturalistic theories of time dilation are "odd!?" Go figure, eh?
One Brow said: "Why would a shipboard traveller make this inference, when what he sees is not in agreement with it? What leads to this inference?"
This is the doppler effect inference, I guess.
Let's start fresh, if we can. Assume each object is moving at a uniform speed in a straight line.
1. If two objects are moving, relative to each other, each will "see" the other's clock as moving more slowly, right?
2. This would not depend on whether they are approaching each other or moving away from each other, because this effect is caused by the relative motion alone.
3. This is because both frames of reference will measure the speed of light the other gives off without regard for the motion of either the source or the reciever.
4. In other words, if object "a" received a light signal from object "b" he would measure the speed of that light beam to be 186,000 mps whether the two were approaching each other at .99c or receding from each other at .99c.
Which of the following is accurate?:
A. The doppler effect plays no part in the how we measure the speed of light.
2. We measure the speed of light differently, depending on the doppler effect.
I said: "Look at this another way: Two people are born at the same instant, at (virually) the same place. One is born on earth, the other on a ship travelling .99c (relative to each other) 100 feet above him. Thereafter, each sees the other as being younger. Question: Who is really younger? Both? Neither? Meaningless question?"
I'm going to answer my own question here in two different ways, giving my reasons for each.
Both? No. It is an inherent contradiction to say each is younger than the other. Even if each perceives the other as being younger, they cannot both "really" be younger, so one or the other is mistaken.
Neither? Yes, on the surface, at least, neither. Neither one is older, and neither one is younger than each other. They have spent an equal amount of time in the universe, and they are the same age.
Meaningless question? Why would the question be "meaningless?" Even if I can't prove which one is really moving, and even if I can't prove that any one object in the universe is absolutely at rest (thereby giving me a reference point for absolute motion) why should the question be "meaningless?" Either they are the same age, or they aren't, whether I can "prove" it, or not.
Why would this question be meaningless when the standard "twin paradox" question is not "meaningless," and various people give you various answers?
The reason one question is supposedly meaningless and the other not is because one tells you which one is "truly" moving and therefore which twin is "truly" younger. In other words, one presupposes an absolute frame of reference, all said and done, and the other doesn't.
My question is not meaningless, it simply doesn't give you sufficient information to provide a meaningful answer. You would simply ask: which one is "really" moving, all you've told me is that they are moving relative to each other. I have to know who (all) is really moving to tell you which one is younger, if either. Of course this posits a "real" speed difference, just as the standard paradox "problem" and solution does. So, apparently even for Einstien and his "moving organism," the notion of "true" motion is not "meaningless."
Next step in answering my question: You give me more information about the "true" motion.
1. You say: "the earth was stationary, the ship was not." My answer: Then then person in the ship is younger.
2. You say: "the earth was moving, not the ship the person was born next to." My answer: then the person on earth is younger.
3. You say: "they were both moving." My answer: Then I need more information in that case, because it depends.
What does it "depend" on? It depends on which one was moving faster, if either.
On the other hand, if you say "I can't give you any more information," then I can never answer the question, so matter how many doppler effect calculations and/or SR/GR formulaes I trot out. If I want to adhere to Einstein's dictum that no frame can be seen as motionless or privileged, then I can't answer your question. Not because it is meaningless, but because I don't have sufficient information to answer it.
If you do give me the information I seek, then you are ignoring Einstein's admonition about "true" motion, i.e., that it doesn't exist and that is "meaningless" to try to address it.
of course everyone with any sense knows that Einstein was full of shit about not being able to detect which of two bodies is "really" moving in relation to the other. If we load up a spaceship with tons of rocket fuel, ignite it, and send it hurling away from us, we know we "accelerated" it and we don't say it is equally plausible, and hence unknowable, that the rocket ignition didn't just send us off hurling away from it.
Once it settles into a uniform speed, and continues across the universe without further acceleration, we will still know that it is moving away from us, and not explain the appearance by saying "Well, who knows? Maybe it has stopped and we are moving away from it now?"
One Brow said: "SR does not predict a "time slippage" or an instant adding of eight years when the ship turns around."
SR doesn't, but GR does, according to your wiki article:
"if the Earth clocks age 1 day less on each leg, the amount that the Earth clocks will lag behind due to speed alone amounts to 2 days. Now the accelerated frame is regarded as truly stationary, and the physical description of what happens at turn-around has to produce a contrary effect of double that amount: 4 days' advancing of the Earth clocks. Then the traveler's clock will end up with a 2-day delay on the Earth clocks, just as special relativity stipulates." Note that this purports to be a "physical description."
If I read this right, "at turn-around" the gross difference in elasped is TWICE the amount of the entire rest of the trip combined, except it is in the opposite direction, and it affects the earth's clock, not the traveller's clock. The speed difference causes a 2-day lag, but the turn-around creates a 4-day speed-up (of earth clocks).
So there does, in fact, seem to be a huge instanteous discontinuity at turn-around posited by GR. This is what Van Flandern is kinda mocking, when he says GR has an explanation that is mathematically consistent, but entirely unpersuasive from the viewpoint of common sense (series of deaths and resurrections).
Wasn't looking for it, but I came across a summary of Bell's "mechanical" explanation for length contraction, if you're interested.
"Bell pointed out that length contraction of objects as well as the lack of length contraction between objects in frame S can be explained physically, using Maxwell's laws. The distorted intermolecular fields cause moving objects to contract — or to become stressed if hindered from doing so."
http://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox
One Brow said: "HIstorically and pedagogically, mass-energy equivalence was a result of SR. I am sure there are ways to derive it outside of SR, but it follows from SR deductively."
Keep in mind that once you have a formula that says E=M, then you have a mass-energy equivalence, whether the conversion multiplier is c, c2, .5c2, or anything else. The multiplier simply quantifies the degree of equivalence and no more; in other words it gives a specific answer to such questions as "how much energy is one ounce of mass equivalent to?"
I already told you that as a historical matter, the concept of mass-energy equivalence had been established long before 1905, but your response simply asserts the opposite. Maybe you should read more history, eh, Eric? This article summarizes some of the history. Some excerpts:
"Preston and De Pretto, following Le Sage, imagined that the universe was filled with an ether of tiny particles which are always moving at speed c....By assuming that every particle has a mass which is the sum of the masses of the ether particles, the authors would conclude that all matter contains an amount of kinetic energy either given by E = mc2 or 2E = mc2 depending on the convention...
Following Thomson and Searle (1896), Wilhelm Wien (1900), Max Abraham (1902), and Hendrik Lorentz (1904) argued that this relation applies to the complete mass of bodies, because all inertial mass is electromagnetic in origin. The formula of the mass–energy-relation given by them was m = (4 / 3)E / c2....
After eliminating the idea of absorption and emission of some sort of Lesagian ether particles, the existence of a huge amount of latent energy, stored within matter, was proposed by Ernest Rutherford and Frederick Soddy in 1903. Rutherford also suggested that this internal energy is stored within normal matter as well. He went on to speculate in 1904: "If it were ever found possible to control at will the rate of disintegration of the radio-elements, an enormous amount of energy could be obtained from a small quantity of matter."
"Independently, Gustave Le Bon in 1905 speculated that atoms could release large amounts of latent energy, reasoning from an all-encompassing qualitative philosophy of physics."
http://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence#History
Einstein is given credit for some new insights into the concept of the equivalency of mass and energy, and rightfully so, but it is simply erroneous to say: "HIstorically and pedagogically, mass-energy equivalence was a result of SR."
... I take you to be saying that even if one only "aged" 10 years and the other 50 years, they would still both "look" 50 years older. ...
No, I'm not saying that. One has experienced ten years and is ten years older, the other has experienced 50 years and is 50 years older.
Of course it's about what he sees, no one said it wasn't. The question is "what does he see (given the doppler effect)? According to the wiki article:
You quoted only the visible effect on the outward trip.
The point is that what he calculates is NOT what he sees. Is there something unclear about that to you?
You quoted only the visible effect on the outward trip.
I said: "The point remains the same: "absolute" motion between the two is presupposed, the earth remains stationary while the rocket moves, and it is insisted that you CANNOT (as Einstein insisted you must) treat the two as equivalent, because one is "really" moving, and the other is "really" stationary.
...
For the record, I never denied this, and never will: "Einstein never insisted that a changing inertial reference frame must be treated as the same as an unchanging reference frame."
So, we agree that Einstein did not insist we treat the two as equivalent.
What Einstein insisted was that the concept of absolute motion was "meaningless," that only relative motion could be detected, and that no one frame of reference could be preferred over another in an attempt to determine which one is "really" moving.
For two inertial frames of reference in motion relative to each other.
The point here is simple. After all the wordy explanations, the question becomes: So why can't we say the earth is moving and not the rocket?
You can, but then it is not just the earth that is accelerating, it is the entire universe, in response to a gravitational field that the ship's propulsion negates, and you have to account for that movement with the energy that comes from the ship's propulsion or accept the sudden appearance of a large mass-energy pehnomenon. If you accept conservation of mass-enegy, the only solution is the frame of reference where the ship moves.
If we do that, which you say is permissible, then the very same analysis will reverse itself, and the earth twin will be younger, not the rocket-ship twin.
I don't know the math and barely understand the concept, but I believe that the huge influx of gravity/acceleration on the rest of the universe, from the viewpoint that the ship is in the inertail reference frame, means that the time shrinkage effect of GR will be stonger than the time dilation effect of SR, and so the planet-bound twin still ages faster.
The answer:
I disagree with your interpretation.
Look at this another way: Two people are born at the same instant, at (virually) the same place. One is born on earth, the other on a ship travelling .99c 100 feet above him. Thereafter, each sees the other as being younger. Question: Who is really younger? Both? Neither? Meaningless question?
You can answer the question for any individual inertial reference frame. There are even some where the two people are the same age. None of those answers will be more correct than any other.
The rocket twin is forced to do conversions.
Only to address a simultaneity that in SR does not really exist.
... some reason to change "hoped to achieve" into "acheived".
Once again you demonstrate a couple of recurring tendencies, Eric:
1. What you don't know about doesn't exist, and
You mean, you used "acheived", but since I didn't know you used "acheived", I assumed you did not use "acheived"? Well shame on me.
2. You don't seek to empirically verify the conclusions you deduce from your presuppositions. You don't have to. They are "necessarily" (in a tautological sense) true.
You mean, I didn't research how much you might have understanted the strength or your position? How foolish of me to think you would try to present the strongest case you could.
3. That, because you already know the answer, there is no real need to read my posts either.
Because, if I had read your post, I would have seen that your really meant "achieved" even though you said "hoped to achieve"?
How could he "demonstrate" something he didn't have, you ever ask yourself that? The web is filled with mechanical models which purport to show how and why objects do vary in length and frequency (time), if you care to look. Just because you have never bothered yourself to seek an explanation does NOT mean they don't exist.
Quite true. However, since we were talking specifcally about Bell, a model produced by someone after Bell died doesn't really fit.
To do this he USED a model (not tried to achieve one).
You meantion a model below on length contraction, and if this is interpreted as the ether distorting electron orbits, it is decent. You still have not presented a model for why going through ether would result in slowing down clocks of different mechanisms in exactly the same way. So far, it a "because the ether slows down clocks". That's magical thinking, not a model.
If speed has "no effect" on a clock then two clocks would read the same whether they had been moving at the same speed or not.
Not if speed affected the local time that one of the clocks measured as opposed to the local time of the other clock.
I think I see what you are saying now, but only in the sense that I know what you are trying to say. It is incomprehensible to me that "time" (which clocks measure) changes the clock. Easy enough to say, but very hard to give any meaningful content to.
Clocks move for mechanical reasons, which are different for different sorts of clocks. They measure time by delay in a spinning wheel reversing direction, or in a voltage gap of a capacitor, or in the changes in electron orbits. Whatever 1 second looks like to us in the intertial frame that sees the moving at some fraction of c, in that frame the seconds are passing normally, and the clocks function normally.
I look at "time" about the same way. It's easy for me to say "time," and easy to attribute all kinds of magical powers to it, as a independently existing "force," but very hard to give meaningful content to when viewed as such. It all sounds incomprehensibly mystical to me when presented in that way.
I certainly don't mean to give that impression. Time is dimension, very much like length, width, or height. It not force that is doing anything.
What you seem to be suggesting is that there is in fact an absolute, independently existing thing called "time," which clocks sense and respond to.
I'll try to be more careful, then. Clocks meaure time like rulers measure distance, by observing the gaps in a specified fashion.
One Brow said: "Why would a shipboard traveller make this inference, when what he sees is not in agreement with it? What leads to this inference?"
This is the doppler effect inference, I guess.
Let's start fresh, if we can. Assume each object is moving at a uniform speed in a straight line.
1. If two objects are moving, relative to each other, each will "see" the other's clock as moving more slowly, right?
2. This would not depend on whether they are approaching each other or moving away from each other, because this effect is caused by the relative motion alone.
3. This is because both frames of reference will measure the speed of light the other gives off without regard for the motion of either the source or the reciever.
4. In other words, if object "a" received a light signal from object "b" he would measure the speed of that light beam to be 186,000 mps whether the two were approaching each other at .99c or receding from each other at .99c.
1. When the line of sight is orthogonal to both intertial frames, yes.
2. I'm not sure about this, but I think that due to the doppler effects, the answer is no. When you are moving away from each other, the visible effects of time dilation are exaggerated, and when moving toward each other, they are reduced and even can be eliminated. For example, if they are approaching each other at .99c, and one person sends a light pulse evey second a person in the other inertial frame, the receiver will get a light pulse every .01 second. When receding, the pusle is received every 1.99 seconds. I believe at that speed there each sender second passes as .1 seconds to the receiver, but the receiver gets 100 pulses in a second, and the receiver sees 10 seconds pass for every second they experience.
Now, that was all flying-by-the-seat-of-my-pants analysis. If you like, we could verify with a physicist (colton on JazzFanz happens to be one, and I know a couple of others on the web).
3. Yes.
4. Yes.
Which of the following is accurate?:
A. The doppler effect plays no part in the how we measure the speed of light.
2. We measure the speed of light differently, depending on the doppler effect.
The speed of light will be measured the same. The light will not be measured the same way.
Neither? Yes, on the surface, at least, neither.
You are assuming a universal reference frame exists in this answer.
Why would this question be meaningless ...
I can't think of a reason it would be meaningless. 'Different answers in different places' is not meaningless.
I have to know who (all) is really moving ...
However, that decision (whether which or both are moving) is arbitrary.
... You give me more information about the "true" motion.
You can arbitrarily chose any intertial reference frame.
Not because it is meaningless, but because I don't have sufficient information to answer it.
I agree.
... then you are ignoring Einstein's admonition about "true" motion, ...
Not as long as you remember the choice of the reference frame is arbitrary.
... Einstein was full of shit about not being able to detect which of two bodies is "really" moving in relation to the other.
I don't believe he said this would always be true, just true in a few special cases.
If we load up a spaceship ... we know we "accelerated" it
Yes, by assuming conservation of mass-energy.
One Brow said: "SR does not predict a "time slippage" or an instant adding of eight years when the ship turns around."
SR doesn't, but GR does, according to your wiki article: ... Note that this purports to be a "physical description."
A physical description that assumes the rocket ship is in an intertial state but massive gravitational fields subjected the rest of the universe to acceleration, and even then it is discussing a calculation based upon an assumption that simultaneity is meaningful, not upon what the shipboard twin sees.
If I read this right, "at turn-around" the gross difference in elasped is TWICE the amount of the entire rest of the trip combined, except it is in the opposite direction, and it affects the earth's clock, not the traveller's clock. The speed difference causes a 2-day lag, but the turn-around creates a 4-day speed-up (of earth clocks).
What happens if the earth stays in an inertial state relative to the ship for 10 days before acceleratinig back? You apparetnly need to tack on two days at the earth's deceleration and two more when the earth accelerates.
In a frame of reference where conservation of mass-evergy doesn't apply, strange things happen, no doubt.
So there does, in fact, seem to be a huge instanteous discontinuity at turn-around posited by GR.
It's not instantaneous, it happens during deceleration/acceleraton (not before or after that), and in a manner you can't detect, and in a frame of reference where mass-energy is not conserved.
This is what Van Flandern is kinda mocking, ... entirely unpersuasive from the viewpoint of common sense ...
Well, the frame where mass-energy is nt conserved would not be within the realm of common sense.
... length contraction between objects in frame S can be explained physically, using Maxwell's laws. The distorted intermolecular fields cause moving objects to contract — or to become stressed if hindered from doing so."
That's interesting, no doubt. He didn't seem to take it to the step or ethereal pressure, though.
Keep in mind that once you have a formula that says E=M, then you have a mass-energy equivalence,
If you prefer, the modern formulation of mass-energy equivalence ss produced by special relativity, both historically and pedagogically.
One Brow said: "You quoted only the visible effect on the outward trip."
No, that's not all I quoted. I also quoted this in the next post. Of course it's all there for you to read whether I quote it or not:
" As seen above, the ship twin can convert his received Doppler-shifted rate to a slower rate of the clock of the distant clock for both red and blue images. If he ignores simultaneity, he might say his twin was aging at the reduced rate throughout the journey and therefore should be younger than him."
See the word "throughout" there?
I said: "What Einstein insisted was that the concept of absolute motion was "meaningless," that only relative motion could be detected, and that no one frame of reference could be preferred over another in an attempt to determine which one is "really" moving.
Your respsonse: "For two inertial frames of reference in motion relative to each other."
Really? So if two objects were in "inertial frames of reference in motion relative to each other" and one of them started accelerating at the rate of one inch per light year, then NOW their respective absolute motions could be detected, and NOW one frame of reference would be preferred over the other, that the idea?
Do you have some quote to that effect?
One Brow said: "You mean, you used "acheived", but since I didn't know you used "acheived", I assumed you did not use "acheived"? Well shame on me."
I don't mean anything of the kind and have no idea why you might think I would know. It does seem obvious that you still don't understand what Bell meant.
One Brow said: "Quite true. However, since we were talking specifcally about Bell, a model produced by someone after Bell died doesn't really fit."
Who said it was "after" Bell--other than your deductions from your "known" premises, I mean?
One Brow said: "Because, if I had read your post, I would have seen that your really meant "achieved" even though you said "hoped to achieve"?
Now I see how misinformed and uncomprehending you are about this.
I will say this one more time, and you can read it yourself (both my statements and those pertaining to Bell which I quoted--more than once. Look at the first one, where I made a point about enforcing pc opinion). One more time, then I give up:
Nobody ever said (as I have already pointed out):
1. That Bell hoped to achieve a model. It said he USED a model, get it?.
2. Bell did not "hope to achieve" a model (see 1, he HAD one already). What he hoped to achieve was the feat of "fending of premature philosophizing about time and space."
3. In short, he USED a model, to demonstrate the reasons why the changes were not caused by the "spatiotemporal environment," and he did this up front hoping to achieve his goal of fending off "premature philosophizing."
It used to be that when I quoted something for you to look at, I assumed you read and understood it, or, that if you didn't, you would listen if someone told you that you had misread it. I can't do that anymore, and now I never have any clue if we're even talking about the same thing.
One Brow said: "A physical description that assumes the rocket ship is in an intertial state but massive gravitational fields subjected the rest of the universe to acceleration, and even then it is discussing a calculation based upon an assumption that simultaneity is meaningful, not upon what the shipboard twin sees."
I agree about what is seen, but why bring that up? The claim you made was not brought up in that context, and had no bearing on it. You made the statement immediately after a lenghy quote of Van Flandern, with the apparent purpose of demonstrating that Van Flandern doesn't know nearly as much about relativity as you do. I can't see where what the observer sees has anything to do with it.
One Brow said: "Well, the frame where mass-energy is nt conserved would not be within the realm of common sense."
But aren't you sayin that's the very frame GR uses to "explain" the time slippage? And, if I read you correctly, the explanation also requires a fictitous notion of "simultaneity" (it seems like you're making my point, now, even though I suspect you still don't know what the point is). Are you saying the explanation made by GR is bogus, then?
Well, to summarize on the "twin paradox" thing:
1. The explanation is not what creates the paradox. There is nothing paradoxical about the "problem" per se. As I said at the outset, no solution (to a paradox) is needed to begin with, given the premises of the problem, because, given those premises, there is no problem.
2. The real paradox has been implicitly resolved at the outset, because the solution (and the problem) presuppose a disallowed presumption, i.e., that you cannot treat either as "preferred." What it really proves, at the end, is that it is false to think that each observer's perceptions are equally valid, because, in truth, one twin is older and one twin is younger. The aging is strictly dependent on who is "really" moving (and how fast) and who isn't. Whether you can ascertain it, or not, the differences are "real" not merely apparent and are the product of "real" motion, merely relative motion.
3. As noted, the "explanation" suggests that it is only "true" motion, not relative motion, which tells you the earth twin is older. This gives rise to another contradiction pertaining to "detection." The reason commonly given for the lack of symmetry is that one is "really" moving and one isn't, AND that this fact can be discerned by way of the inertial forces experienced at turn-around. This also contradicts the premise that only "relative" motion can be detected, and that there is no way to ascertain "true" motion (which of the two is "really" moving).
Initially the paradox is posed this way: If both frames of reference are equally valid, because true motion is undetectable, and if each frame of reference causes one twin to see his twin as younger, then you are saying it is "equally valid" to suggest that each is younger than the other. But that paradox is not really even addressed. It is disposed of by hypothesis. The "solution" basically ends up saying: "No the two are not equally valid (forget we ever said that). The travelling twin is wrong in his perceptions and the stay at home is right (his twin "really is" younger). And we know this because we can detect that the younger one is "really" moving (forget that we ever said it couldn't be detected)."
One Brow said: "You still have not presented a model for why going through ether would result in slowing down clocks of different mechanisms in exactly the same way. So far, it a "because the ether slows down clocks". That's magical thinking, not a model."
1. I don't intend to "present a model," if that's what you're expecting. Research the matter yourself if you want one.
2. You refer to ether, but it's not still 1905, ya know? As I understand it, in the neo-lorentizian view what is sometimes called "ether" really just reduces to gravitional effects. I realize that "gravity" is a very suspect concept, all on it's own, but LR doesn't appeal to it any more than GR does.
One Brow said: "Clocks move for mechanical reasons, which are different for different sorts of clocks."
One clock stays stationary, one is accelerated and then returns. I trust that you agree that they will read differently, irrespective of the way the clock is designed.
Why should mere speed "cause" that? Did this happen by "magic?" Yeah, I spoze. I guess it just a question of whether you want to attribute "magical" powers to time or gravity.
One Brow said: "They measure time by delay in a spinning wheel reversing direction, or in a voltage gap of a capacitor, or in the changes in electron orbits."
Not sure I understand this, but I don't think I agree. As I see it, all time-keepers are based upon the presumed frequency of a consistently recurring event. Not sure how "delay" would be involved here, unless maybe you are referring to "duration." I would have to guess that any changing of the measurement of time therefore means a changing of that frequency (from what it was initially presumed to be to something else). The time-keeper would still be based on regularly recurring events, but the rate of the occurrence of those events has changed. Temperature can directly affect some types (ultimately even all types, I spoze) of clocks, but not because time itself has slowed down or speeded up.
I asked: "2. We measure the speed of light differently, depending on the doppler effect.
You said: The speed of light will be measured the same. The light will not be measured the same way.
If we adhere to SR, then we know in advance that we will measure the speed the same. We have to, it's a postulate.
But of course speed is merely distance/time. How do we determine these? I mean, we know the answer to the division problem (186,000 mps), in advance, and don't even have to think about that (given SR postulates), but how do we know how "far" something is from us or how much "time" it took the light to get to us? Does the doppler effect change the way we calculate the distance? The way we calculate the time? Both?
I mean, like, do I know a star is 5 light years away from us (a measurement of distance) because I know it took light from it 5 years to get here? How do I know when the light I am seeing now left, exactly?
Does it matter if the star is approaching me, receding, or staying equidistant? If it matters, how do I know if it was doing that 5 years ago? Or, in the case of distant stars, say 100 million years ago.
One Brow said: "If you prefer, the modern formulation of mass-energy equivalence ss produced by special relativity."
Which is just another way of saying that only Einstien's formulation is Einstien's formulation, aint it? Kinda goes without sayin, I spoze.
From what I understand, Einstien's derivation of e = mc2 (when he finally reached it after previous formulations) was mathematically erronous, but I guess that's neither here nor there, except to wonder how he can erroneously "derive" such a magnificent formula. I mean, did he actually derive it mathematically, or did he just do so inductively and then make a mistaken attempt to show that he "derived" it deductively?
Thinkin about how the doppler effect affects what I actually see:
I see a distant star. I can't "see" it as moving away from me or toward me--it just look stationary; it's not getting bigger, or smaller, or anything like that which might suggest that it's distance from me is constantly changing. I am told that it is moving away from me at a great speed (due to calculations), but I have no way of knowing whether the light impulses hitting my eyeballs are doing so more or less frequently than they would if the star was stationary; they don't look any different, either way. The star is not "flickering" or displaying any other type of behavior than would tell me, on the basis of my eyesight, that it's moving away. It doesn't appear to me that the light particles are hitting my eyeballs any more or less often than I see them to be (which is constant).
One Brow said: "I certainly don't mean to give that impression. Time is dimension, very much like length, width, or height. It not force that is doing anything. I'll try to be more careful, then. Clocks meaure time like rulers measure distance, by observing the gaps in a specified fashion."
OK. A very accurate clock, synchronized with a second one which stays behind, is sent into orbit at a high altitude and at a high rate of speed. After 1 year it splashes down in the ocean and we retrieve it. When that happens, it will no longer agree with the second clock, right? I assume you agree, but tell me if you don't.
SR would explain this as being due in part to it's altitude (less gravity) and in part to it's increased rate of speed, as I understand it.
How does "time" cause the speed element? How does "gravity" cause the altitude element? How does a "dimension" effectuate an observable difference in the number of ticks made by each clock? How does "gravity" do it, for that matter?
If you can give a satisfactory (to you) answer to the gravity portion of the foregoing question, then you should have little trouble accepting the LR explanation, "magical," or not.
It's the "time" thing I'm really curious to hear your response to, though. How does time, qua time, "cause" the clock to slow down?
Going back to Van Flanern's "deaths and resurrections" comment, I guess he's saying something like this:
If you are in orbit around a "stationary" star at a rate of .9c then at certain times you will be approaching earth, and at certain time you will be receding from earth. Say earth is 4 light years away.
Now, if you were stationary on the surface of the star, the light hitting your eyes would have left earth 4 years ago. But if you are receding from the earth (and the "stationary" star), the light which left earth 4 years ago, and is "just now" hitting the surface of the star, cannot be seen by you because you have outran them. The only light from earth which you can "now" see had to leave earth MORE than 4 years ago. This situation reverses itself when you are approaching earth at a high rate of speed. So, as I said, I guess he is talking about the doppler effect, or some variation of it.
" If he ignores simultaneity, he might say his twin was aging at the reduced rate throughout the journey and therefore should be younger than him."
Due to the Doppler shifting, the ship twin sees rapid aging on the return trip, as far as I can tell.
... and NOW one frame of reference would be preferred over the other, that the idea?
Do you have some quote to that effect?
In terms of special relativity only, I don't have a quote to that effect, and I don't think that "absolute motion" could be detected anyway, but yes, the inertial frame becomes preferred for reasons of conservation of mass-energy (from what I recall, anyhow).
It does seem obvious that you still don't understand what Bell meant.
Naturally, you feel your understanding is superior.
Who said it was "after" Bell--other than your deductions from your "known" premises, I mean?
You can always correct me when I'm wrong. I have never focused on the timeline of the attempts to develop a model for LR/LET, much less juxtaposed them with Bell's lifetime.
Now I see how misinformed and uncomprehending you are about this.
I will say this one more time, and you can read it yourself (both my statements and those pertaining to Bell which I quoted--more than once. Look at the first one, where I made a point about enforcing pc opinion). One more time, then I give up:
Nobody ever said (as I have already pointed out):
1. That Bell hoped to achieve a model. It said he USED a model, get it?.
No, your quote, and the paper, said Bell hoped to achieve a pedagogical goal by using a model. It does *not* say he had the model in hand to present. In fact, it says Bell only had the small bits that could be the beginning of the model.
The final ingredient is the so-called clock hypothesis (and its analogue for rods). This is the claim that when a clock is accelerating, the effect of motion on the rate of the clock is no more than that associated with its instantaneous velocity—the acceleration adds nothing. This allows for the identification of the integration of the metric along an arbitrary time-like curve—not just a geodesic—with the proper time. This hypothesis is no less required in general relativity than it is in the special theory. The only work that I am aware of that provides the rudiments of a constructive justification of this hypothesis within the theory of matter is Bell’s 1976 essay.
Further, if Bell had the model in hand, I doubt that he woyuld be so incompetent in applying it that he would not have achieved his goal of showing there was an alternate model. If you have two ways of factoring trinomials, and you write both of them on the board and tell your students that they should choose which method they are the most comfortable with, yet the class walks away thinking there is only one way to factor polynomials and the other way is just wrong, you have taught that class very poorly. Maybe most of the students prefer one way or the other (in fact, just about all of them), but they at least know both will work.
It used to be that when I quoted something for you to look at, I assumed you read and understood it, or, that if you didn't, you would listen if someone told you that you had misread it. I can't do that anymore, and now I never have any clue if we're even talking about the same thing.
It has been a long time since I have assumed we, or for that matter any two people, will read the same passage and get the same meaning out of it. It's almost like universals are interpreted differently in each brain, or something. At any rate, hashing out the differences is part of the fun and the learning.
... with the apparent purpose of demonstrating that Van Flandern doesn't know nearly as much about relativity as you do. ...
If the Van Flandern "time slip" referred only to the calculation based on an imposed simultaneity, and not to what the observer actually saw, then I mis-read him. Also, noting that he seems to have made a false claim, after you asked specifically about them, does not mean I think I know more about it than he.
But aren't you sayin that's the very frame GR uses to "explain" the time slippage?
It's the frame where time slippage becomes the necessary device to explain all the observations. It is no more nonsensical than the frame from which it is derived.
Are you saying the explanation made by GR is bogus, then?
In that the frame in which GR is being used is bogus, the results of GR are bogus, sure. GIGO.
1. The explanation is not what creates the paradox. There is nothing paradoxical about the "problem" per se. As I said at the outset, no solution (to a paradox) is needed to begin with, given the premises of the problem, because, given those premises, there is no problem.
I agree.
2. The real paradox has been implicitly resolved at the outset, because the solution (and the problem) presuppose a disallowed presumption, i.e., that you cannot treat either as "preferred." What it really proves, at the end, is that it is false to think that each observer's perceptions are equally valid, because, in truth, one twin is older and one twin is younger. The aging is strictly dependent on who is "really" moving (and how fast) and who isn't. Whether you can ascertain it, or not, the differences are "real" not merely apparent and are the product of "real" motion, merely relative motion.
That's certainly one point of view. However, even if you adopt the that there is only relative motion, and that no inertial reference frame is preferred, the twin paradox reaches the same resolution. So, this interpretation is not necessary to the understanding of the paradox.
3. As noted, the "explanation" suggests that it is only "true" motion, not relative motion, which tells you the earth twin is older. This gives rise to another contradiction pertaining to "detection." The reason commonly given for the lack of symmetry is that one is "really" moving and one isn't, AND that this fact can be discerned by way of the inertial forces experienced at turn-around. This also contradicts the premise that only "relative" motion can be detected, and that there is no way to ascertain "true" motion (which of the two is "really" moving).
I have never heard a relativity claim that a change in inertial frames can not be detected (just that it can not be distinguished from the effects of gravity). So, since one twin undergoes 3-4 rounds of acceleration detectable from his own reference frame, ane the other twin does not, the equations treat the reference frames unequally.
Initially the paradox is posed this way: If both frames of reference are equally valid, because true motion is undetectable, and if each frame of reference causes one twin to see his twin as younger, then you are saying it is "equally valid" to suggest that each is younger than the other.
Only if both frames are inertial.
But that paradox is not really even addressed. It is disposed of by hypothesis. The "solution" basically ends up saying: "No the two are not equally valid (forget we ever said that). The travelling twin is wrong in his perceptions and the stay at home is right (his twin "really is" younger). And we know this because we can detect that the younger one is "really" moving (forget that we ever said it couldn't be detected)."
Actually, the solution is that the question of who is younger at any given moment when the twins are not together will be observer-dependent.
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