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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«Oldest ‹Older 1401 – 1600 of 1677 Newer› Newest»I've already quoted this, but you missed the point (and will again, I expect). Wiki discussed three versions of the EP (the weak, the Einstein, and the strong, versions).
With respect to the Einstien version it says: "The outcome of any local non-gravitational experiment in a freely falling laboratory is independent of the velocity of the laboratory and its location in spacetime."
It then defines "local:" Here "local" has a very special meaning: not only must the experiment not look outside the laboratory, but it must also be small compared to variations in the gravitational field, tidal forces, so that the entire laboratory is freely falling. It also implies the absence of interactions with "external" fields other than the gravitational field."
So, you can't tell if you're in a gravitational field if, and ONLY IF, among other things, you are prevented from doing experiments which are "non-gravitational." Whooda thunk!?
It other words, it aint sayin sheeit. Wiki also notes: "So the original equivalence principle, as described by Einstein, concluded that free-fall and inertial motion were physically equivalent...This is not strictly true, because massive bodies give rise to tidal effects (caused by variations in the strength and direction of the gravitational field) which are absent from an accelerating spaceship in deep space. Although the equivalence principle guided the development of general relativity, it is not a founding principle of relativity..."
http://en.wikipedia.org/wiki/Equivalence_principle
Again, in other words, it aint shit. Nonetheless I'm sure you won't be disinclined to keep from asserting that: "All non-rotational motion is relative, the EP (which does not address rotational motion) is valid locally."
How could you EVER say otherwise? Once you say something, there's no retraction, come hell or high water. Even Al gave up on his original formulations, but you won't.
Edit: Meant to say: "So, you can't tell if you're in a gravitational field if, and ONLY IF, among other things, you are limited to doing experiments which are "non-gravitational." Whooda thunk!?"
I might as well also mention that you cannot, repeat CANNOT, have any observational access to your surroundings (outside the tiny box you're in). It's kinda like sayin you can't tell if it's really day or night outside if you're buried 6 feet deep in a pine box, ya know?
Only a fool would conclude that therefore it is IMPOSSIBLE for it to be either day or night outside.
The whole "all accelerated motion is relative" ambitions Al had just turned into absurdity. It really boils down to a guy buried in a pine box not knowing anything about what's going on outside, and then concluding that, since he doesn't know, anything could be goin on outside, and since "anything" "could be" going on, we are quite justified in saying whatever we dream up IS going on (since it could be, based on the best one who is deliberately kept ignorant knows). Nice try, Al. Thanks for playing. To repeat what the Minnesota Professor who has done extensive research on the matter and who writes encyclopedia articles on the topic says:
"In 1907, Einstein set out to fully relativize all motion, no matter whether uniform or accelerated. After five failed attempts between 1907 and 1918, he finally threw in the towel around 1920, setting himself a new goal. For the rest of his life he searched for a classical field theory unifying gravity and electromagnetism. As he struggled to relativize motion, Einstein had to readjust both his approach and his objectives at almost every step along the way;he got himself hopelessly confused at times; he fooled himself with fallacious arguments and sloppy calculations;and he committed what he later allegedly called the biggest blunder of his career: he introduced the cosmological constant."
No doubt I could dredge up many more authorities making the same point, and your invariant response would simply be:
One Brow said: "All non-rotational motion is relative!"
That's virtually the ONLY thing you have said in this thread, and I swear you have said it, in one variation or another, at least 500 times.
You can say the same, but it wouldn't be the same. Al made a fair case for the indistinguishability of inertial frames, but SR regards acceleration as absolute.
So, now you do understand why Pat and Chris are equally right? Dare I hope?
The attempt to "make" accelerated motion strictly "relative" seems to have failed miserably.
If you mean the attempt to include rotational motion, begun mostly after Einstein completed his field equations for GR, then I agree.
Of course indistinguishability as a matter of fact in a particular, abstract case is NOT the same indistinguishability in theory or in principle. Something you don't seem to understand.
I don't? Do I also fail to understand that indistinguishability with regard to one set of criteria is not indistinguishability with regard to all sets of criteria? Do I fail to understand that, simply because the resulotion of certain problems does not depend on distinguishing between certain types of phenomena, that other problems will require this distinguishment?
Wait, that seems to be more you than me, for all three.
First you say this: "I have seen nothing from you to change this opinion." Then you say this: "Nothing annoys you more than my reading the reference material and noting that it conirms what I have been telling you, it seems."
Are you SERIOUS!?
Completely.
I have given you references which flatly contradicts not only what you have been saying, but further contradicts what you claim all physicists say?
Except, you haven't. I have taken great pains over dozens of comment to explain why those references are saying the same thing I am saying, sometimes with different terminology, and how you have misread those references. You are just now realizing this?
Can you really not even read?
I not only read them, I understand them. You don't seem to.
One Brow said: "Rotational motion is the type of motion that Einstien acknowledged he could not describe relativistically. I suppose Bondi could be talking about other types of motion, but I assumed he was speaking competently."
Are you suggesting that if Bondi was not talking only about rotational motion, then he is incompetent?
The reason General Realtivity is not truly general is that not every type of motion is relative. That is Bondi's point, and the point of a few other authors. Bondi thought the nomencalture for the theory was inappropriate, that you should not call something general when it has major exceptions. That's all his paragraph said.
Yes, you are, but I want you to repeat it. I want to you make it clear just how deep your wildly exagerated, but unwarranted, esteem for your own seriously misguided opinions runs, and just how quick you are to call a giant in the field of relativity incompetent if he does not agree with your crap.
It's not my crap, it's the understanding of GR by physicists. I said I assumed he was speaking competently, not that he was incompetent. Further, speaking incompetently on nomencalture would not have made Bondi incompetent. Also, being a giant does not make him immune to error.
Your hyperolic ARROGANCE truly amazes me.
With your lack of reading skills, you must be amazed quite often.
One Brow said: "All non-rotational motion is relative, the EP (which does not address rotational motion) is valid locally, and the using the conservation od mass-energy to choose one reference frame over another that violates strikes me as valid reasoning. That you think these ideas are in opposition somehow is your ignorance."
Yeah, right. My ignorance and all of those experts and researchers I just cited.
None of those researchers you cited would disagree with those statements.
Once again you merely demonstrate your inability to read and comprhend. The author quoted said NOTHING about using the conservation of energy to "choose one reference frame over another. He said, that Einstien (try very hard to read this carefully):
"...came to abandon his original idea of reducing all non-uniform motion to gravity..."
I have been confirming and acknowledging this for half a page of quotes now. Yes, he abandoned the idea that rotational motion could be reduced to gravity, or even be ascribed relativistically.
Are you that blind? You have been telling me that with only two objects (let alone just one) it would be impossible to tell which one was moving and, heh, therefore IMPOSSIBLE for one to actually be moving faster than another. And all this, according to you was "dictated" by relativity theory.
Actually, I have been saying all along that it is only possible after you first choose a coordinate system/rest frame. Further, I have never said this is "dictated" by relativity theory, I said the answers in relativity theory don't need you to choose the coordinate system first, because all the choices come out the same anyhow.
Given only two objects and no rest frame to compare them to, the reason it is impossible to say which is faster has nothing to do with relativity theory. It comes from the relative nature of what speed is, but speed having a relative nature is not dictated by relativity theory. Rather, the inherently relative nature of speed dictates what relativity theory can do.
And if you think all these physicists expressing their rejection of GR as a theory of relative motion are talking ONLY about rotation, then, again, you simply demonstrate that you understand nothing I provide you with to read.
Actually, I understand it better than you.
Your way of conceding that you were wrong is always the same (in the unlikely event that you ever do concede it): You simply deny that you ever said what you said.
Most of the time, I only need to deny your understanding of what I said.
The problem is, as these phsyicists I cited have pointed out, his attempt to say accelerated motion is relative failed. His idea was that if you could substitute an imaginary psuedo-gravitational field for acceleration, that made acceleration relative. Fraid not. Insofar as it attempts to "relativize" accelerated motion GR is a failure, they say.
If those physicists had been talking about that aspect of GR, I would agree.
You could have a thousand experts and 1,000,000 facts disproving your opinion
The summary of thousand experts, and a million facts, wielded by a person who doesn't understand what is being said and what the facts mean, will still be the incorrectly interpeted summary of the person who doesn't understand. I accept the opinions of these experts and the implicaitons of the facts. I do not accept your interpretation, because it does not truly reflect what they are saying. You may claim that I insist on reading them through my own lens, but so do you.
It's not *my* definition which matters. See if you can understand this sentence from the math guy:
I am having this conversation with you, not the math guy. I am asking you to pick a definition, and stick to it. I am happy to say that an inertial frame is the following of a geodeisic, I used that for pages until colton agreed with you that it was an improper usage. I am also comfortable using it to specify only motion in a straight line at a constant speed (whcih may or may not be along a geodeisic), which a page ago was your preferred interpretation, and which colton supported. I onlyu ask that *you* pick one of these for the purpose of our discussion.
"the only difference being that in general relativity the inertial geodesics imply a curved manifold, whereas the inertial geodesics in the earlier theories were consistent with a globally flat manifold."
There are, according to him, "inertial geodeics in BOTH SR and GR, but they are differnt things. In SR, Al's definition of "inertia" in simply Newton's. He basically reverses his defintion in GR, as I have repeatedly pointed out. Standing alone "geodesic" means nothing in particular. You must first specify the type of spacetime you are assuming (flat or curved)>
You misunderstand the math guy here. You don't have to choose, because the GR geodeisic exists in either flat or curved spacetime. GR does not require spacetime to be curved, it merely can operate there, when SR can not. GR also operates equally well in a flat spacetime. The meaning of geodeisic is unchanged between a flact and a curved spacetime.
According to Euclid, a line (straight line) is the "shortest distance between two points." This does not change in GR. Nongeodesics in GR are "crooked lines" (accelerated). Geodesics (inertial) in GR are "straight" (with the qualification being that "straight" means "straighest possible" in a curved medium). Do you get this? Do you get that there is no ONE definition of geodesic?
Again, you are fooling yourself by your false distinction of SR and GR. There is one definition of geodeisic. The appearance of the geodeisic will be straight in flat spacetime and curved in curved spacetime, but they are the same thing. That you think there is a definition of geodeisic in flat spacetime that is different from the one in curved spacetime is a measure of how badly you don't get it.
From what I read, astronomers repeatedly conclude that the vast majority of space is "flat."
In the sense that there is very little curvature, sure.
Even with GR, Al also thought space was "flat" in places. Depending on what type of space a body is in, it's "geodesic" might be "straight" according to euclidean geometry or "straight" according to reimannian geometry.
Technically, the geometry of space would be Lobachevskian (negative), not Riemannian (positive). Out side of that, sure. However, this is not because the definition of a geodeisic is different, but because the same definition of the geodeisic, applied in Euclidean vs. Lobachevskian space, produces different results.
What Al originally tried to do, with his EP, was "reduce" all accelerated frames to an SR frame, on a (VERY STRICTLY, that is to say "infintesimal) "local" basis. From that standpoint, accelerated particles were moving at a uniform speed in a (euclidean) straight line, with no external forces acting upon them. Nice try, Al.
On that basis, GR works, and has been working for decades.
Even a sharply curved line will be straight if you only look at an "infintesimal" segment of it, ya know?
As long as it is smooth, sure. By smooth, I mean all the derivatives exist.
One variation of the EP, one which still accepted, is the equvalence (proportionately, at least) of inertial and gravitational mass. The EP is still considered "valid" in this sense. Most physicists reject the idea (as Al himself eventually did) that gravity is equivalent to acceleration for the purpose of claiming that all accelerated motion is "relative."
You say that, but the expert pages references say otherwise.
...This is not strictly true, because massive bodies give rise to tidal effects (caused by variations in the strength and direction of the gravitational field)
Again, in other words, it aint shit. Nonetheless I'm sure you won't be disinclined to keep from asserting that: "All non-rotational motion is relative, the EP (which does not address rotational motion) is valid locally."
You can only notice tidal effects from variations in the strength and direction of a gravitational field non-locally, as the article acknowledged.
How could you EVER say otherwise? Once you say something, there's no retraction, come hell or high water. Even Al gave up on his original formulations, but you won't.
I have given up many assertions over the years. I've even devoted blog posts to my errors. Is it really that I think I'm immune to error, or just that, in this particular issue, you have not made a convincing case, and maybe don't understand it as well as you think?
Edit: Meant to say: "So, you can't tell if you're in a gravitational field if, and ONLY IF, among other things, you are limited to doing experiments which are "non-gravitational." Whooda thunk!?"
The non-gravitational experiements that always come out the same, locally. If you perform experiments on gravity specifically, there might be an interaction between any local gravitational field and the exterior gravitational field that allows you to detect the exterior field. Whyu do you think this is an issue?
I might as well also mention that you cannot, repeat CANNOT, have any observational access to your surroundings (outside the tiny box you're in). It's kinda like sayin you can't tell if it's really day or night outside if you're buried 6 feet deep in a pine box, ya know?
Only a fool would conclude that therefore it is IMPOSSIBLE for it to be either day or night outside.
Because there are other ways, outside the pine box, to make that conclusion.
The whole "all accelerated motion is relative" ambitions Al had just turned into absurdity. It really boils down to a guy buried in a pine box not knowing anything about what's going on outside, and then concluding that, since he doesn't know, anything could be goin on outside, and since "anything" "could be" going on, we are quite justified in saying whatever we dream up IS going on (since it could be, based on the best one who is deliberately kept ignorant knows).
No, relativity theory says that even though anything could be going on, we can nevertheless draw certain conclusions, regardless of what acutally is going on.
"In 1907, Einstein set out to fully relativize all motion, no matter whether uniform or accelerated. After five failed attempts between 1907 and 1918, he finally threw in the towel around 1920, setting himself a new goal. For the rest of his life he searched for a classical field theory unifying gravity and electromagnetism. As he struggled to relativize motion, Einstein had to readjust both his approach and his objectives at almost every step along the way;he got himself hopelessly confused at times; he fooled himself with fallacious arguments and sloppy calculations;and he committed what he later allegedly called the biggest blunder of his career: he introduced the cosmological constant."
Do you read this as saying no motion is relativizable, or just certain types of motion are not? What type of motion what Einstein working on when he "threw in the towel"? What type of motion was it that required the cosmological constant? Where does this say Einstien failed to show acceleration, specifically, is relativizable?
One Brow said: "Meanhile, even when colton confirms my interpretations, you just disregard them. You can keep pretending I don't understand. I know better."
I didn't see where Colton supported your interpretation of the twins in any way, shape, or fashion.
To see which is “really younger”, you would have to bring the two people into the same frame, next to each other.
I may be misunderstanding the situation. Are we still talking about Pat & Chris moving relative to each other? In that case, I would say both are correct.
I don’t have much personal experience with G.R., but judging from the Einstein dialog you steered me to above, all frames (even non inertial ones) are equally valid, as long as you account for the (fictitious?) gravitational fields that arise when you have an accelerating frame. That’s not to say all frames are equally useful, though. The simplest-behaving ones are probably the most useful.
The question of "How is it different from being in an inertial environment?" is an excellent one. The answer must be "There is no difference", because (as is clear from viewing the situation in frame K) U1 *is* in an inertial environment.
Yes, S.R. is a part of G.R. You can say G.R. reduces to S.R. when you remove gravity and non-inertial reference frames (or equivalently, when space-time is flat).
Unless I misunderstood you somehow, you said different things about all of those points. If you have really agreed with all of those all along, we have been arguing about very little.
He said accelerated motion was critical to the solution and denied that the "relative motion alone" could account for it. He certainly did NOT say, as you claimed, that even if the ship twin stayed stationary while the earth moved the ship twin would STILL be younger. That is just prima facie absurd, yet you appear to cling to it, ignoring what Colton said.
He said he would replace "really moving" with accelerated, or chaning inertial references frames, and then refers to this as not following the geodeisic. These are all relative concepts.
One Brow said: "Are you suggesting that if Bondi was not talking only about rotational motion, then he is incompetent?"
Just answer the question. Was he talking ONLY about rotational motion?
If he was not, is he incompetent?
One Brow said: "Are you suggesting that if Bondi was not talking only about rotational motion, then he is incompetent?"
Just answer the question. Was he talking ONLY about rotational motion?
If he was not, is he incompetent?
Looking at the context, let's see:
I don't have Bondi's original paper, so I am assuming that the author is using the quote in conext here. The context that the author provides is not all motion was relative. The motion that was conceded not to be relative in 1921 was rotational motion. Further, every analysis of scenarios we have looked at so far, like the twin paradox, say that the answers you get while calculating in frame K' are the same as the answers you get while calculating in frame K, so that motion is in fact relative. Since "general" is often interpreted as "universally applicable", and the relativity in GR is not universally applicable (and specifically not applicable to rotational motion), that seems to be a sufficently broad class of exceptions to say the "general" of GR is a misnomer. Since Bondi specifically complained about a "physically meaningless phrase", not a meaningless theory or even idea, I'm going to take him at face vaule: he is saying that the "general" in GR is not a truly appropriate label.
As for the second question, since Bondi was not talking about acceleration/gravity with his comment, from what I can tell, the hypothesis is void, and the conclusion moot.
My quote your previous comment disappeared.
"...by 1921 Einstein had already conceded, however grudgingly, that his general theory
of relativity, worked out between 1907 and 1918, does NOT make all motion relative....the prominent relativist Sir Hermann Bondi (1979) wrote: "It is rather late to change the name of Einstein's theory of gravitation, but general
relativity is a physically meaningless phrase that can only be viewed as a historical
memento of a curious philosophical observation" (181)
One Brow said: "I have been confirming and acknowledging this for half a page of quotes now. Yes, he abandoned the idea that rotational motion could be reduced to gravity, or even be ascribed relativistically."
This is NOT solely about rotational motion and the sources I've cited make that clear. Maybe you need to ask Colton what they mean when they talk about "accelerated" motion. Acceleration may include, but is by no means limited to, rotational motion.
You simply misread everything so as to comport (or so you think) with your pre-existing misconceptions. Where does Bondi mention "rotational" motion? Where does Synge? Where does the Minnesota Professor (did you even read his paper)? The math guy tells you that there is an "absolute" distinction between accelerated (nongeodesic) and inertial (geodesic) motion (or maybe the other guy, I'm not looking at it now). This is about the EP, get it? Al tried to use the EP to relativize all motion, including accelerated motion. They believe that attempt failed and merely reflected Al's devotion to an "obscure philosophy."
The EP did turn out to be theoretically valuable as a method of explaining the proportionality of inertial mass and gravitational mass (known to, but not really "explained" by, Gallileo, Newton, and many others before them). I already made a post about this (twice), citing wiki, but you don't respond to that.
There is simply no way to discuss this with you rationally. Because you KNOW that accelerated motion is completely relative, you KNOW that everyone who claims otherwise is really saying the opposite of what they are saying. They agree with you, naturally, despite their denials.
I asked: Just answer the question. Was he talking ONLY about rotational motion?
You responded: "the relativity in GR is not universally applicable (and specifically not applicable to rotational motion).."
So what is your answer? Is it, YES, I am claiming that Bondi was only talking about rotational motion?
Just answer the question.
One Brow said: "He said he would replace "really moving" with accelerated, or chaning inertial references frames, and then refers to this as not following the geodeisic. These are all relative concepts.
1. That's not all he said.
2. Acceleration, inertial frames, and "following a geodesic" are NOT unique to SR or GR. Newton incorporated all of them. Nor are they "relative" in the sense that they only have meaning in relation to each other and no independent meaning.
Do you have a point? Colton said one was moving out and back, and this was "absolutely" essential to the answer given.
Colton said: "To see which is “really younger”, you would have to bring the two people into the same frame, next to each other."
I asked him a follow-up question about this, seeking his rationale, not merely his conclusion. I am still awaiting that response. Until I get that clarification, I really don't know how he intended this (epistemologically or ontologically).
Referring to Colton, I said: "He certainly did NOT say, as you claimed, that even if the ship twin stayed stationary while the earth moved the ship twin would STILL be younger. That is just prima facie absurd, yet you appear to cling to it, ignoring what Colton said."
1. Do you take him to be saying otherwise?
2. Do you still cling to your original understanding?
Colton appears to be confused by Einstein's claim to have "completely resolved the paradox." Who wouldn't be? It absurd and even when wiki and others cite it they do so with a caveat that modern physicists do not but it.
Colton: "The answer must be "There is no difference", because (as is clear from viewing the situation in frame K) U1 *is* in an inertial environment....I don’t have much personal experience with G.R."
Elsewhere Colton specifically questioned trying to contrast a GR (K') setting with an SR one (K).
He certainly didn't convey that he was trying to give a definitive answer here.
I asked him a follow-up question about this situation also.
edit: "It absurd and even when wiki and others cite it they do so with a caveat that modern physicists do not buy it.
Colton said: "To see which is “really younger”, you would have to bring the two people into the same frame, next to each other."
Yes, of course you would have to bring them back together "to see" them.
My question is about what SR/GR would PREDICT, not what would be visually confirmed.
I said: "My question is about what SR/GR would PREDICT, not what would be visually confirmed."
Neither wiki,nor Colton that I could tell, nor any other relativist that I am aware of, had/has any qualms whatsoever talking about the aging of the travelling twin at the time he reached his "turn-around' point, despite the fact that he had not yet "returned." The return is irrelevant to the prediction, given the stated presumption that is the travelling twin who has been accelerated to a higher relative speed.
One Brow said: "Further, every analysis of scenarios we have looked at so far, like the twin paradox, say that the answers you get while calculating in frame K' are the same as the answers you get while calculating in frame K, so that motion is in fact relative."
We were going through this 1200 posts ago, and you still can't see the obvious. The SR portion (i.e., the time dilation due SOLELY to a higher relative speed) of each is the same. It would be "the same" for each if you picked the other clock to start with, too.
You do NOT get the "same" answer, because it is NOT the same question is K and K'. In K' Einstein simply inserts an imaginary event which OFFSETS and OVERCOMPENSATES for the speed dilation effects with "gravitational" contraction effects. The SR portion does NOT change, get it? I have little doubt that you do NOT get it.
In Einstien's own example, if you eliminate the bogus "gravitational" contraction effects the MOVING clock will record less time, due to its MOTION. Get it? Stupid question on my part, no doubt.
In theory, you could think up millions of questions that a person would answer "yes" too. The fact that the answers are the same does not prove that the question was the same.
One Brow asked: "Where does this say Einstien failed to show acceleration, specifically, is relativizable?"
Uhhh, right there in the first sentence, mebbe?
"In 1907, Einstein set out to fully relativize all motion, no matter whether uniform or accelerated. After five failed attempts between 1907 and 1918, he finally threw in the towel around 1920..."
It's a waste to cite you something that you can't read, but nonetheless assert that the author is saying what you have been saying.
One Brow said: "The non-gravitational experiements that always come out the same, locally. If you perform experiments on gravity specifically, there might be an interaction between any local gravitational field and the exterior gravitational field that allows you to detect the exterior field. Whyu do you think this is an issue?"
I've been telling you why it is an issue for hundreds of posts now. Why do you ask again?
Al tried to use the EP as a springboard to claiming that even accelerated motion is relative. GR, insofar as it pretends to be a "theory of relative motion" doesn't fly. To the extent Al tried to use the claim of the "equivalency" of acceleration and gravity, he was wrong.
I said: "To the extent Al tried to use the claim of the "equivalency" of acceleration and gravity, he was wrong."
Al tried to turn what a person deprived of all means of relevant information "knows" (or, actually "doesn't know") about gravity, into what gravity really *is.* This is NOT a solid foundation for a physical theory, although it may suffice (dependending on your tastes and gullibility) as a foundation for a desired philosophical/ontological theory.
One Brow said: "I have been confirming and acknowledging this for half a page of quotes now. Yes, he abandoned the idea that rotational motion could be reduced to gravity, or even be ascribed relativistically."
This is NOT solely about rotational motion and the sources I've cited make that clear. Maybe you need to ask Colton what they mean when they talk about "accelerated" motion. Acceleration may include, but is by no means limited to, rotational motion.
I agree that acceleration includes rotational motion. I agree that this means not all acceleration can be described relatively. I say this to forstall the usual misinterpretations, so I hopy you understand that part.
"Some sorts of acceleration can not be described relatively" does *not* imply "no sort of acceleration can be described relatively".
You simply misread everything so as to comport (or so you think) with your pre-existing misconceptions. Where does Bondi mention "rotational" motion?
Bondi does not mention motion at all in that quote. He only mentions how the name is not accurate.
Where does Synge? Where does the Minnesota Professor (did you even read his paper)?
Where do they specifically say that *no* acceleration is relative?
There is simply no way to discuss this with you rationally. Because you KNOW that accelerated motion is completely relative, you KNOW that everyone who claims otherwise is really saying the opposite of what they are saying. They agree with you, naturally, despite their denials.
There are no denials. There is just the over-exaggeration by you. Not all types of acceleration can be describe relatively, so you jump to say that none can. This is despite seeing, in page after page, various scientists use relativity of a certain types of acceleration directly.
You are relying on correctly interpreting quotes that do not say what you want them to say, and ignoring work that people acutally have put onscreen for you.
I asked: Just answer the question. Was he talking ONLY about rotational motion?
You responded: "the relativity in GR is not universally applicable (and specifically not applicable to rotational motion).."
So what is your answer? Is it, YES, I am claiming that Bondi was only talking about rotational motion?
Just answer the question.
My answer is: Bondi was not talking about motion, directly, at all. He was talking about how GR was named.
Now, Ihave gone into why, from what I can gather, he would have thought the name inappropriate, and that does have to do with rotational motion.
One Brow said: "He said he would replace "really moving" with accelerated, or chaning inertial references frames, and then refers to this as not following the geodeisic. These are all relative concepts.
1. That's not all he said.
Of course not.
2. Acceleration, inertial frames, and "following a geodesic" are NOT unique to SR or GR. Newton incorporated all of them.
Agreed.
Nor are they "relative" in the sense that they only have meaning in relation to each other and no independent meaning.
Not sure what you mean here.
Do you have a point? Colton said one was moving out and back, and this was "absolutely" essential to the answer given.
Yes, and then qualified that absolutely to list aspects of the movement that are relative as being the essential parts.
Referring to Colton, I said: "He certainly did NOT say, as you claimed, that even if the ship twin stayed stationary while the earth moved the ship twin would STILL be younger. That is just prima facie absurd, yet you appear to cling to it, ignoring what Colton said."
1. Do you take him to be saying otherwise?
2. Do you still cling to your original understanding?
If you mean some scenario where a rocket is attahced to earth, we agree on that anyhow.
If you mean an Eartha/Astro scenario, where Eartha is moved solely by freefall, thus staying in the geodeisic, while Astro stays inertial, leaving the geodeisic, I believe he answered that when he said that the person in the geodeisic always experiences more time. However, if you like I will fashion a question to reflect this scenario specifically.
Colton appears to be confused by Einstein's claim to have "completely resolved the paradox." Who wouldn't be? It absurd and even when wiki and others cite it they do so with a caveat that modern physicists do not buy it.
You keep thinking that modern physicist reject K' because of the internal logic. However, the reasons to reject K' are external to the relativistic concerns (for example, conservaiton of mass-energy). Physicists accept K' as a legitimate relativistic description that comes to the same answers as K.
Colton: "The answer must be "There is no difference", because (as is clear from viewing the situation in frame K) U1 *is* in an inertial environment....I don’t have much personal experience with G.R."
Elsewhere Colton specifically questioned trying to contrast a GR (K') setting with an SR one (K).
He certainly didn't convey that he was trying to give a definitive answer here.
You think "must be" indicates he is uncertain of the answer? He might be uncertain of the derivation of that answer in the frame K', but he is very clear that, since K' and K describe the same events, they give the same answer.
Yes, of course you would have to bring them back together "to see" them.
My question is about what SR/GR would PREDICT, not what would be visually confirmed.
SR/GR predicts that different people will see Pat or Chris as younger when they are spearated, and that there is no reason to say any of them are more correct.
Neither wiki,nor Colton that I could tell, nor any other relativist that I am aware of, had/has any qualms whatsoever talking about the aging of the travelling twin at the time he reached his "turn-around' point, despite the fact that he had not yet "returned."
The travelling twin changes his inertial frame when he leaves earth. So even before turn-around, he has left the geodeisic.
The return is irrelevant to the prediction, given the stated presumption that is the travelling twin who has been accelerated to a higher relative speed.
Exactly. The traveling twin was acelerated compared to the previous rest frame shared by both twins, left the geodeisic, and is therefore experiencing less time.
We were going through this 1200 posts ago, and you still can't see the obvious. The SR portion (i.e., the time dilation due SOLELY to a higher relative speed) of each is the same. It would be "the same" for each if you picked the other clock to start with, too.
You do NOT get the "same" answer, because it is NOT the same question is K and K'. In K' Einstein simply inserts an imaginary event which OFFSETS and OVERCOMPENSATES for the speed dilation effects with "gravitational" contraction effects. The SR portion does NOT change, get it? I have little doubt that you do NOT get it.
Here is what I get from you, as I did 1200 posts ago: You are still trying to create some artificial distinction between an "SR portion" and a "GR portion" so you can impute something called "higher relative speed" to U1, which is still sophist nonsense. You still think that, since there is no known event (an ontological object) that creates the effects (what can be measured) of K', this means the effects observed in K' are not real, and this is somehow meaningful to the analysis of K' or makes K' an inferior analysis, in ways you can't really articulate.
However, the effects of K' are real, even though the event used to justify those effects is imaginary. This is why physicists do not use frames like K', they don't like real effects of imaginary events. Ths does make K' wrong or invalid. It does not change that the conclusions you get from K' must match those from K (this should be obviously true even to you). It makes K' less desirable for reasons outside of the relativistic description of K'
In Einstien's own example, if you eliminate the bogus "gravitational" contraction effects
The you are no longer discussing K'. If you change the initial conditions, you change the answer, sure.
One Brow asked: "Where does this say Einstien failed to show acceleration, specifically, is relativizable?"
Uhhh, right there in the first sentence, mebbe?
Sorry, I dropped a phrase. I'll try to be more careful.
Where does this say Einstien failed to show any kind of acceleration, specifically, is relativizable?
I've been telling you why it is an issue for hundreds of posts now. Why do you ask again?
You specified why the local interaction of gravitational fields is a problem for a version of the EP that says it is not addressing the local interaction of gravitational fields? I missed that.
Al tried to use the EP as a springboard to claiming that even accelerated motion is relative. GR, insofar as it pretends to be a "theory of relative motion" doesn't fly. To the extent Al tried to use the claim of the "equivalency" of acceleration and gravity, he was wrong.
Yes, the EP only applies to certain sorts of acceleration, not to all types, and in particular not rotational.
I await your quotes that *no* type of aceleration is relative.
Al tried to turn what a person deprived of all means of relevant information "knows" (or, actually "doesn't know") about gravity, into what gravity really *is.* This is NOT a solid foundation for a physical theory, although it may suffice (dependending on your tastes and gullibility) as a foundation for a desired philosophical/ontological theory.
If by "relevant information" you mean information that relativity theory does not use, you can say the ame thing about SR. GR takes information about how the behavior of gravity is highly similar to that of acceleration, and and uses that to say some things about what gravity must be. That seems like a fairly reasonable thing to do.
One Brow said: "You can only notice tidal effects from variations in the strength and direction of a gravitational field non-locally, as the article acknowledged."
"Notice" is a pretty vague word, especially when it entails being prevented from "noticing" by looking out the window or conducting gravitational experiments. But, either way, so what?
Gravity PRODUCES tidal effects, "noticed" or not. Acceleration does NOT produce tidal effects. Acceleration and gravity are not the "same." It is improper to conclude that acceleration IS gravity, because of what someone "notices," in any event, but ESPECIALLY when he has been artificially deprived of all means of noticing.
The fact that a blind man can't see the sky does NOT mean:
1. That there is no sky
2. That it is "equally valid" to say that there is a sky and there aint no sky
3. That what a man "sees" is the sole determining criterion for deciding what reallly is.
Well, unless you're a metaphysical philosopher with a VERY STRONG desire to "prove" something you want to claim to be true, maybe, ya know?
Gravity PRODUCES tidal effects, "noticed" or not.
The gravitational fields of masses produce tidal effect due to their non-constancy. Tidal effects are not produced by gravity itself.
Acceleration does NOT produce tidal effects.
Actually, rotational acceleration does. If you spin an elevator slowly, on the inside it looks very much like you are seeing tidal effects.
The fact that a blind man can't see the sky does NOT mean:
The the blind man can deduce nothing at all about the sky.
One Brow said: "My answer is: Bondi was not talking about motion, directly, at all. He was talking about how GR was named."
And you base your claim about what Bondi was NOT talking about on what?
1. Your deductions from your personal apriori assumptions?
2. Your reading of his paper?
Are you retracting your orginal claim that Bondi WAS, in fact, talking about (ONLY) rotational motion?
If you want a fuller explanation for why I said Bondi was referring to rotation motion, I gave that in the January 14, 2010 12:38 PM comment on this page. I believe that comment answers your questions, but if you feel it doesn't, where do you see the gap?
One Brow said: "Exactly. The traveling twin was acelerated compared to the previous rest frame shared by both twins, left the geodeisic, and is therefore experiencing less time."
So when you say "left the geodesic" all you really mean is that the travelling twin accelerated, achieved a higher relative speed than his twin and BECAUSE he is moving at a higher relative speed, he, and he alone (not his twin) experiences time dilation due to motion?"
I trying to get at the real world CAUSE of the age difference here, not some substitute for explanation such as "left the geodesic."
One Brow said: "You keep thinking that modern physicist reject K' because of the internal logic. However, the reasons to reject K' are external to the relativistic concerns (for example, conservaiton of mass-energy). Physicists accept K' as a legitimate relativistic description that comes to the same answers as K."
NO, THAT'S NOT the reason, and I have repeatedly quoted to you the actual reasons they give, which boil down to this:
Al's "pseudo-gravitational field" in contrived, bogus, and has nothing to do with physics or phsyical reality as interpreted by modern physicists. It is not even GR--it is a philosophical position taken by Al in a failed attempt to "relativize" accelerated motion.
One Brow said: "The gravitational fields of masses produce tidal effect due to their non-constancy. Tidal effects are not produced by gravity itself."
What does this mean? Two objects, dropped in an elevator in space which is accelerated by gravity, will see the two objects converge on each other because they are both moving toward the CENTER of the gravitational mass. If the same spaceship is simply being accelerated far from any gravitational mass, the two objects will NOT converge on each other.
I said: "Two objects, dropped in an elevator in space which is accelerated by gravity, will see the two objects converge on each.."
I should have said in an elevator parked on earth (not "in space")
I said: "It is not even GR--it is a philosophical position taken by Al in a failed attempt to "relativize" accelerated motion."
Al himself acknowledges this in the remainder of his dialogue with his critics. He readily admits that it would be absurd to claim that the earth is motionless while the heavens spins, but think there is great theoretical and philosophical significance to the claim that it is nonetheless "theoretically possible."
The perfect basis for a "theoretical" jaunt into the realm of metaphysics, sure, but.....
One Brow said: "If you want a fuller explanation for why I said Bondi was referring to rotation motion, I gave that in the January 14, 2010 12:38 PM comment on this page. I believe that comment answers your questions, but if you feel it doesn't, where do you see the gap?"
Well, just curious. You started by saying one thing, and then making the opposite claim. I think the answer is clear about your basis for your claims. You have NOT read the article, and you declarations about it's contents are pure speculation, not to mention wrong speculation. Nothing new, really. You constantly make unqualified statements of fact without a basis.
I pointed out:"...came to abandon his original idea of reducing all non-uniform motion to gravity..."
You responded: I have been confirming and acknowledging this for half a page of quotes now. Yes, he abandoned the idea that rotational motion could be reduced to gravity, or even be ascribed relativistically
Hint: "all non-uniform motion" is NOT "rotational motion"
This just get more surreal all the time. YOU say: Previously you claimed an inertial frame was motion in a striaght line at a constant speed. That is not what a geodeisic is.
You say a geodesic is NOT motion in a straight line at a constant speed. I respond to this, saying it can be that, and explaining the difference between geodesic in flat vs curved spacetime. In flat spacetime it IS what you just said it wasn't.
Then you tell me what I just told you, and claim *I* misunderstood the math guy.
One Brow said: "You misunderstand the math guy here. You don't have to choose, because the GR geodeisic exists in either flat or curved spacetime. GR does not require spacetime to be curved, it merely can operate there, when SR can not. GR also operates equally well in a flat spacetime. The meaning of geodeisic is unchanged between a flact and a curved spacetime."
Yeah, that's what I just said to help clear up the confusion introduced by your claim that: "motion in a striaght line at a constant speed...is NOT what a geodeisic is."
By the way, I never did say quiet what you claimed I said anyway, because you left out the additional condition that a particle must be (1)free from external influences,(2) moving at a uniform speed, and (3) in a "straight" (also "straightest possible," when dealing in curved space) to be considered as following a geodesic (inertial) path.
It is the failure of the "motionless" clock in frame K' to meet condition number (1) in Al's example that prevents it from being a "geodesic" (as Colton seemed to suggest that it "must" be). On the other hand, the "motionless" clock in frame K is definitely, as Colton said, geodesic (inertial). As Colton rightly noted, this is NOT comparing apples to apples.
What Al tried to say was that EVERY inertial frame (in SR) can be "seen as" an accelerating one AND that every accelerating frame (in SR) can be "seen as" an inertial one and that "therefore" there are no inertial frames and there are no accelerated frames. Pure nonsense, and a bogus claim to begin with, as pointed out by the math guy.
One Brow asked: "What type of motion was it that required the cosmological constant?"
Well, Eric, you could read the article, ya know? It is here: http://philsci-archive.pitt.edu/archive/00004377/01/LoveMinusZero.pdf
Einstien realized and conceded that, under SR, acceleration was absolute. This disturbed him on philosophical grounds. He wanted, in particular to relativize acceleration (rotational motion was not his big concern).
According to this professor, 3 things were required in order to do that:
1. The EP
2. A material source for (cause of) the EP, and
3. Generally co-varient gravitational field equations.
Among other problems he ran into was this:
"When Einstein wrote it, he was laboring under the illusion that, simply by virtue of its general covariance, the new theory made all motion relative...The other condition mentioned above, however, was not met...In the fall of 1916, in the course of an exchange with the Dutch astronomer Willem de Sitter, Einstein was forced to admit this....He thereupon modified his field equations (without compromising their general covariance) by adding a term
with the so-called cosmological constant (Einstein 1917b). Einstein's hope was that
these new field equations would not allow any gravitational fields without material
sources....A few months later, it became clear that even the modied equations
do not satisfy this principle. Within another year or so, Einstein came to accept
that general relativity, the crowning achievement of his career, did not banish
absolute motion from physics after all."
If you read this, in context, the problem is with trying to claim that acceleration = gravitation, and the concern is NOT with rotational motion, per se. The guy goes on to say:
"When two objects are in relative non-uniform motion, this additional structure allows us to determine whether the first, the second, or
both are actually moving non-uniformly. In this sense, motion in general relativity is as absolute as it was in special relativity."
Kinda what the math guy said. Also note that the claim here is that GR allows us to determine if "the first, the second, or
both are actually moving non-uniformly [my insertion: i.e. accelerating)."
Mach's principle was never satisfied, even though Einstien thought for a while that it had been. Without that satisfaction, "acceleration with respect to absolute space would simply
be replaced by the equally objectionable notion of fictitious gravitational fields." This is what De Sitter called "a cure worse than the disease," and this is what the wiki article and the other physicist is pointed out.
Same guy goes on to say: "Even though the equivalence principle could not be used for its
original purpose of making all motion relative, Einstein did make it the cornerstone of a spectacular new theory of gravity that is still with us today."
This is the distinction Bondi and Synge were making, and this explains their reference to "curious" and "obscure" philosophy (i.e., the philosophy that led Einstein to claim that bogus gravitational fields were "real" so as to argue for the complete relativization of accelerated motion).
One Brow said: "Exactly. The traveling twin was acelerated compared to the previous rest frame shared by both twins, left the geodeisic, and is therefore experiencing less time."
So when you say "left the geodesic" all you really mean is that the travelling twin accelerated, achieved a higher relative speed than his twin and BECAUSE he is moving at a higher relative speed, he, and he alone (not his twin) experiences time dilation due to motion?"
I couldn't mean that, because "achieved a higher relative speed than his twin" is meaningless unless yo specify a reference frame, and you did not specify one.. The relative speed of the spaceship twin to the earth twin is exactly the same as the relative speed of the earth twin to the spaceship twin. Leaving the geodeisic has meaning, accelerating has meaning, and in this particular scenario they happen to be the same act. Until you specify a reference frame, "higher realtive speed has no meaning".
I trying to get at the real world CAUSE of the age difference here, not some substitute for explanation such as "left the geodesic."
Leaving the geodeisic is the real-world cause.
One Brow said: "You keep thinking that modern physicist reject K' because of the internal logic. However, the reasons to reject K' are external to the relativistic concerns (for example, conservaiton of mass-energy). Physicists accept K' as a legitimate relativistic description that comes to the same answers as K."
NO, THAT'S NOT the reason, and I have repeatedly quoted to you the actual reasons they give, which boil down to this:
Al's "pseudo-gravitational field" in contrived, bogus, and has nothing to do with physics or phsyical reality as interpreted by modern physicists. It is not even GR--it is a philosophical position taken by Al in a failed attempt to "relativize" accelerated motion.
Why is Al's "pseudo-gravitational field" in contrived, bogus, and lacking anything to do with physics or phsyical reality as interpreted by modern physicists? Is it for any relativistic reason? In what way does relativity fail to describe the scenario?
You continue to betray your ignorance of physics and the interpretation of physicists. If the attempt to relativize motion in K' is such a failure, why is it repeated in, for example, the wiki article on the twin paradox?
One Brow said: "The gravitational fields of masses produce tidal effect due to their non-constancy. Tidal effects are not produced by gravity itself."
What does this mean? Two objects, dropped in an elevator in space which is accelerated by gravity, will see the two objects converge on each other because they are both moving toward the CENTER of the gravitational mass. If the same spaceship is simply being accelerated far from any gravitational mass, the two objects will NOT converge on each other.
Why is Al's "pseudo-gravitational field" in contrived, bogus, and lacking anything to do with physics or phsyical reality as interpreted by modern physicists? Is it for any relativistic reason? In what way does relativity fail to describe the scenario?
1) That is not a tidal effect.
2) two objects will converge to each other in the spaceship being accelerated, because of their innate gravitational attraction. However, the rate of the convergence may be different. This would be a gravitational experiement, which we have already acknowledged is not a part of the EP.
He readily admits that it would be absurd to claim that the earth is motionless while the heavens spins, but think there is great theoretical and philosophical significance to the claim that it is nonetheless "theoretically possible."
He then abandons this project as impossible, the physics of rotation not being relative.
not to mention wrong speculation.
You have a copy of Bondi's article? Or is this just more speculation on your part.
Not that it matters. Even if youhad the article, you would probablyh understand it no better than any other work on the subject.
Hint: "all non-uniform motion" is NOT "rotational motion"
Hint: the opposite of "all non-uniform motion" is not "no uniform motion".
YOU say: Previously you claimed an inertial frame was motion in a striaght line at a constant speed. That is not what a geodeisic is.
You say a geodesic is NOT motion in a straight line at a constant speed. I respond to this, saying it can be that, and explaining the difference between geodesic in flat vs curved spacetime. In flat spacetime it IS what you just said it wasn't.
The path of the geodeisic becomes a straight line in flat spacetime. The apple becomes red when it ripens. This does not mean that redness is the apple. The straight line is the shape of the geodeisic in flat spacetime, it is not what the geodeisic is.
Yeah, that's what I just said to help clear up the confusion introduced by your claim that: "motion in a striaght line at a constant speed...is NOT what a geodeisic is."
As long as the difference between the geodeisic (a path) and linearity (a property) is clear.
By the way, I never did say quiet what you claimed I said anyway, because you left out the additional condition that a particle must be (1)free from external influences,(2) moving at a uniform speed, and (3) in a "straight" (also "straightest possible," when dealing in curved space) to be considered as following a geodesic (inertial) path.
1) free from non-gravitational external influences, 2) a uniform speed is not necessary, and 3) "straight" in the sense of not have an empirically, locally detectabe change of path. A highly elliptical orbit is still a geodeisic, even thought the orbiting body is affected by gravity, moving at a varying speed compared to the body it orbits, and is elliptical in shape.
It is the failure of the "motionless" clock in frame K' to meet condition number (1) in Al's example that prevents it from being a "geodesic" (as Colton seemed to suggest that it "must" be). On the other hand, the "motionless" clock in frame K is definitely, as Colton said, geodesic (inertial). As Colton rightly noted, this is NOT comparing apples to apples.
So, you don't understand what a geodeisic is, apparently.
that every accelerating frame (in SR) can be "seen as" an inertial one
Yes, this is not true of every acceleratiing frame.
One Brow asked: "What type of motion was it that required the cosmological constant?"
Well, Eric, you could read the article, ya know?
Read it, and I know the answer.
If you read this, in context, the problem is with trying to claim that acceleration = gravitation, and the concern is NOT with rotational motion, per se. The guy goes on to say:
"When two objects are in relative non-uniform motion, this additional structure allows us to determine whether the first, the second, or both are actually moving non-uniformly. In this sense, motion in general relativity is as absolute as it was in special relativity."
Full quote: If Mach's principle were satisfied, this field could be fully reduced to its material sources and all motion would be relative. But Mach's principle is not satisfied and the inertio-gravitational field exists in addition to its sources. When two objects are in relative non-uniform motion, this additional structure allows us to determine whether the first, the second, or both are actually moving non-uniformly. In this sense, motion in general relativity is as absolute as it was in special relativity.
The "additional structure" is from the failure of Mach's principle. Do you remember what Mach's principle is? Is Mach's principle, or its failure, significant in K'? Do you really think this means no accelerated motion is relative, or does it refer to the type of accelerated motion discussed in mach's principle?
I know the answers, but I want to see if you can derive them.
Mach's principle was never satisfied, even though Einstien thought for a while that it had been. Without that satisfaction, "acceleration with respect to absolute space would simply be replaced by the equally objectionable notion of fictitious gravitational fields." This is what De Sitter called "a cure worse than the disease," and this is what the wiki article and the other physicist is pointed out.
Do you know what Mach's principle is? Hint: it's on page 23 and following in the article. Don't blame the messenger.
Same guy goes on to say: "Even though the equivalence principle could not be used for its
original purpose of making all motion relative, Einstein did make it the cornerstone of a spectacular new theory of gravity that is still with us today."
This is the distinction Bondi and Synge were making, and this explains their reference to "curious" and "obscure" philosophy (i.e., the philosophy that led Einstein to claim that bogus gravitational fields were "real" so as to argue for the complete relativization of accelerated motion).
Again, you are confusing that not all acceleration is relative with no acceleration being relative.
One Brow said: "I couldn't mean that, because "achieved a higher relative speed than his twin" is meaningless unless yo specify a reference frame, and you did not specify one."
Is it possible that you can ever stop with this pedantic, meaningless quibbling crap? I don't HAVE to specify one, it is built into the whole problem. In any other case where you feel a temptation to respond with this casuistry, just pick any frame you care to...the earth, the moon, the sun, some distant galaxy, Pat, Chris, I don't care. Pick any instead of simply saying I didn't pick one. It is irrelevant in the pat and chris scenario in any event (I know you don't think so, but that's only because you can't distinguish epistemological ignorance from ontological possibility).
If A is separating from B at half the speed of light, there are multiple possibilities, ONE of which must be the case. A could be "at rest" while B is travelling at a speed relative to B of .5c. It "could" be the opposite. It could be anything in between. But if the are separating, at least one of them is moving. Chances are good that one is moving faster than the other, whether YOU can pinpoint who it is or not. All I've said is the whoever is moving faster will age more slowly. NO frame is needed to say that.
If you still can't see this, you never will. As always, you think YOUR personal lack of knowledge is the beginning and end of all possible reality. By doing so, you, in effect, deny that relativity is a viable theory, because you are in, in effect, saying that SR does NOT predict that whoever is moving faster will age less slowly when it DOES say and predict that.
Nothing could be more "meaningless" than your incessant droning about "meaninglessness." This is a cheap cop-out, and is itself "meaningless."
For about the 50th time (why do I bother?):
If A and B are separating from each other...
1. Is at least one moving?
2. If not, are both at rest, and both deluded, because all motion is illusory?
3. If so, is it POSSIBLE that one is moving faster? Pick your own God damn "frame of reference," if you still erroneously think that is ABSOLUTELY necessary to answer the question, and shut up about that.
One Brow said: "Leaving the geodeisic is the real-world cause."
Only an utter fool could possibly say this. But you have repeatedly demonstrated that you have no idea of what a "cause" is, so what else is new?
One Brow said: "You continue to betray your ignorance of physics and the interpretation of physicists. If the attempt to relativize motion in K' is such a failure, why is it repeated in, for example, the wiki article on the twin paradox?"
I've already answered that about 10 times, even in the post(s) you are currently responding to. Because wiki expressly notes that Al's postulation of the "reality" of bogus, "psuedo-gravitational" fields is NOT accepted by modern physicists. They make this a point of specific EMPHASIS:
"It should be emphasized that according to Einstein's explanation, this gravitational field is just as "real" as any other field, but in modern interpretation it is only perceptual because it is caused by the traveling twin's acceleration." (wiki)
The other (Stella) physicist emphasizes the same point. This could be specifically brought to your attention 10,000 more times, and you would still ask the same question.
One Brow said: "Why is Al's "pseudo-gravitational field" in contrived, bogus, and lacking anything to do with physics or phsyical reality as interpreted by modern physicists?"
If you still can't see that after the many times is has been explained for you by me and by the experts I cite, you never will. That's the way it is with chumps...they can never figure out that they have been played, and insist they have NOT been played.
One Brow said: "Read it, and I know the answer"
Is the answer, which you know, that "it is ONLY rotational motion?"
You quote this the following. Read it. Try to understand it. Then answer your own questions and don't bother me with them.
"When two objects are in relative non-uniform motion, this additional structure allows us to determine whether the first, the second, or both are actually moving non-uniformly. In this sense, motion in general relativity is as absolute as it was in special relativity."
Is it possible that you can ever stop with this pedantic, meaningless quibbling crap? I don't HAVE to specify one, it is built into the whole problem.
Refernece frames are never built-in. They can be arbitrarily chosen.
It is irrelevant in the pat and chris scenario in any event (I know you don't think so, but that's only because you can't distinguish epistemological ignorance from ontological possibility).
Not just me, but colton as well. You know, teh physicist you thought we were supposed to accept as the expert. Oh, you have "questions" for him. Of course. Once you explain it properly, no doubt the physicist will come around to your understanding. It can't possibly be that you are wrong.
If A is separating from B at half the speed of light, there are multiple possibilities, ONE of which must be the case.
Why must one of them represent "the case"? What do you think a reference frame is?
A could be "at rest" while B is travelling at a speed relative to B of .5c. It "could" be the opposite. It could be anything in between. But if the are separating, at least one of them is moving.
I agree that in any reasonable reference frame, one of them will be moving.
Chances are good that one is moving faster than the other, whether YOU can pinpoint who it is or not.
The gobbledeegook pouras out again.
All I've said is the whoever is moving faster will age more slowly. NO frame is needed to say that.
If you insist on their being a single ontological answer, the correct answer is that, as long as Pat and Chris both stay in the geodeisic (assuming they don't approach too near a gravitational body, this will form a straight line), they age at the same rate ontologically. Neither will age faster than the other. Geodeisic travel always experiences maximal time passage.
If you still can't see this, you never will.
You seem to think I don't understand your points. I do understand them. I understand them well enough to know they are wrong, and why they are wrong. They are wrong because, at their heart, you are trying to insert a specific type of absolute motion that does not exist. The problem is not with my understanding, it is with your thinking.
As always, you think YOUR personal lack of knowledge is the beginning and end of all possible reality.
My personal knowledge is not relevant here. What is relevant is the actual nature of reality, and the degree to which it fits the modle of reality you have created.
By doing so, you, in effect, deny that relativity is a viable theory, because you are in, in effect, saying that SR does NOT predict that whoever is moving faster will age less slowly when it DOES say and predict that.
SR prdicts that whoever leaves the inertial path will age more slowly, whether that person is moving faster or slower than the one who stays inertial.
Nothing could be more "meaningless" than your incessant droning about "meaninglessness." This is a cheap cop-out, and is itself "meaningless."
An even cheaper cop-out is to completely fail to be able to give a meaning for a phrase, call it common sense, and then whine when you are called out for your phrase having no meaning. Here's a simple one: interstellar rock A is moving compared to instellar rock B. When you say rock A moves faster than rock B without using a reference frame, what does that mean?
For about the 50th time (why do I bother?):
If A and B are separating from each other...
1. Is at least one moving?
In any reasonable reference frame.
2. If not, are both at rest, and both deluded, because all motion is illusory?
Even in a crazy reference frame that would see both of them at rest, the motion becomes part fo the reference frame itself, and is therefore still present in the description.
3. If so, is it POSSIBLE that one is moving faster? Pick your own God damn "frame of reference," if you still erroneously think that is ABSOLUTELY necessary to answer the question, and shut up about that.
In an infinite number of reference frames, A will be moving faster. In an infinite number of reference frames, B will be moving faster. In an infinite number of reference frames, they will move at the same speed. If you pick a reference frame at random using a version of geometric probability, you are 50% likely to pick a frame where A is faster and 50% likely are to pick one where B is faster, the probability of choosing one at random where they move the same is 0.
One Brow said: "Leaving the geodeisic is the real-world cause."
Only an utter fool could possibly say this. But you have repeatedly demonstrated that you have no idea of what a "cause" is, so what else is new?
Meanwhile, you have reapeated demonstrated you don't know what a geodeisic is, but even so you are sure leaving it can't be a cause. So, I take yor insult with all the merit your knowledge of the subject warrants.
One Brow said: "You continue to betray your ignorance of physics and the interpretation of physicists. If the attempt to relativize motion in K' is such a failure, why is it repeated in, for example, the wiki article on the twin paradox?"
I've already answered that about 10 times, even in the post(s) you are currently responding to. Because wiki expressly notes that Al's postulation of the "reality" of bogus, "psuedo-gravitational" fields is NOT accepted by modern physicists.
They devote three paragraphs and repeat the entire example, in detail, just to show that they dont accept it? That really works for you? Tha'ts your "common sense" opinion of the authors of the pages? Why didn't they devote paragraphs to ether theory in that article? They reject that as well. Do you think they might see some value in the "accelerated observer viewpoint" even though they reject the ontological reality of it?
This could be specifically brought to your attention 10,000 more times, and you would still ask the same question.
Because you are bypassing the answer. Why do they devote time to it at all, if they feel it is utterly wrong?
One Brow said: "Why is Al's "pseudo-gravitational field" in contrived, bogus, and lacking anything to do with physics or phsyical reality as interpreted by modern physicists?"
If you still can't see that after the many times is has been explained for you by me and by the experts I cite, you never will.
The question was rhetorical, I answered back on the second page of the comments.
Is the answer, which you know, that "it is ONLY rotational motion?"
Did you read page 23 and following?
You quote this the following. Read it. Try to understand it. Then answer your own questions and don't bother me with them.
"When two objects are in relative non-uniform motion, this additional structure allows us to determine whether the first, the second, or both are actually moving non-uniformly. In this sense, motion in general relativity is as absolute as it was in special relativity."
You think pulling it from it's context a second time will make the context-stripping more legitimate? What type of motion is the sentence referring to here? What type of motion does the failure of mach's principle refer to? Does "not all types of acceleration" imply "no types of acceleration"?
Here's an example to think about:
Two ships moving at .2c are about to pass you (all speeds are in your reference frame). One of them (the talker) stops for ten minutes to say hello, then speeds off at .6c and catches the quiet one after five minutes. So, teh talker spends ten minutes going slower than the quiet one, and five minutes going faster. When the talker cataches up, his clock will show less time has passed than the quiet one.
Funny thing is, the quiet guy disagrees. When the talker engages you, according to quiet guy the talker speed up to .2c to drift alonside you, and then hightails it back to you. So really, the talker was always moving faster than quiet guy.
May you and quietguy need to duke this one out, eh? What the talker's clock moving slower than quietguy's clock *really* slower or faster when he was talking to you?
Or, maybe this means all time is meaningless and relative, isn't that your usual shtick? Yeah, that's it.
Notice: nothing but pure SR here, BTW.
One Brow said: "If you insist on their being a single ontological answer, the correct answer is that, as long as Pat and Chris both stay in the geodeisic (assuming they don't approach too near a gravitational body, this will form a straight line), they age at the same rate ontologically....Geodeisic travel always experiences maximal time passage."
This contention has been disproven by experiment and merely re-iterates the same confusion you have displayed since we first started talking about the GPS system.
Once a satellite launched from earth enters orbit, it is in a geodesic, right? And yet less time passes for it EVERY day (not just once) thereafter, compared to time on earth. Why? Because, relative to the earth, it is now "going faster." It's clock does run CONTINOUSLY slower.
Same with the wiki twin, for every day or year that passes, the travelling twin ages less even though, for the vast majority of the time they are separated, the travelling twin is in geodesic.
Question: In each of these scenarios, is the earth also on a geodesic path?
This contention has been disproven by experiment and merely re-iterates the same confusion you have displayed since we first started talking about the GPS system.
Once a satellite launched from earth enters orbit, it is in a geodesic, right? And yet less time passes for it EVERY day (not just once) thereafter, compared to time on earth. Why? Because, relative to the earth, it is now "going faster." It's clock does run CONTINOUSLY slower.
You're remembering wrong: "... the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)!"
http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html
The orbiting clocks, in the geodeisic, exerpience more time than us, who are not in the geodeisic (at least while staying on the surface of the planet). Still, feel free to keep commenting on my confusion. Why stop now?
... for the vast majority of the time they are separated, the travelling twin is in geodesic.
Vast majority =/= all.
Question: In each of these scenarios, is the earth also on a geodesic path?
You mean, is the clock on the earth (for GPS) or the clock of the earth twin on a geodeisic. The answer to the first is definitely no. For the second, we treat the clock in the thought experiment as if it were on the geodeisic. If it were a real clock on the real earth, it would not be, and the numbers coming out of the twin travel would be altered because of that.
One Brow said: " a specific type of absolute motion that does not exist....they age at the same rate ontologically
And you were informed about the non-existence of absolute motion, and the "ontological" aging by whom, exactly? God?
One Brow said: "they age at the same rate ontologically"
A nice philosophical assertion, no doubt, but this claim is undermined by the twin paradox. There is asymmetry in the two clocks, not an equal passage of time, as a truly relational theory would predict. Each "sees" the other's clock as running slower in the twin paradox, but only one of those clocks actually *is* running slower, while the other is running faster.
No, physicists. They are much more fallible, though.
Also, I did not say that no type absolute motion exists. I referred to the sorta-absolute-motion you try to bring in that doesn't require a specific reference frame.
A nice philosophical assertion, no doubt, but this claim is undermined by the twin paradox.
Teh twin paradox does not involve different indivdual staying in different geodeisics.
There is asymmetry in the two clocks, not an equal passage of time, as a truly relational theory would predict. Each "sees" the other's clock as running slower in the twin paradox, but only one of those clocks actually *is* running slower, while the other is running faster.
Actually, after turn-around, the traveling twin sees the earth twin's clock running much, much faster than his clock on the return journey. So, his seeing the clock running faster matches teh clock running faster.
One Brow said: "You're remembering wrong: "... the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)!"
I'm talking about the 7, you can't understand that?
One Brow said: "You're remembering wrong: "... the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)!"
So you're saying the earth clock is NOT on a geodesic, the satellite is on geodesic, but the nongeodesic ages more, that the idea? How does that square with this claim?:
One Brow said: "Geodeisic travel always experiences maximal time passage."
I'm talking about the 7, you can't understand that?
That's like saying the Cavaliers won the game last night because they outscorwed the Jazz between the 3:00 and 2:00 marks in the 4th quarter.
So you're saying the earth clock is NOT on a geodesic,
Correct.
the satellite is on geodesic,
Correct.
but the nongeodesic ages more, that the idea?
Correct.
How does that square with this claim?:
One Brow said: "Geodeisic travel always experiences maximal time passage."
It squares by saying basically the same thing? Maximal time passage would age more, compared to less than maximal time passage.
One Brow said: "Each "sees" the other's clock as running slower in the twin paradox, but only one of those clocks actually *is* running slower, while the other is running faster."
Back to equivocation on the word "sees" (which I put in scare-quotes for a reason) by bringing the the doppler effect AND the relativistic effects. Let me put it another way: Each "sees" the other's clock as running slower and the other's distances as be foreshortened in the direction of motion.
Of course the question is not really even about what mistaken observers "see." It is about one aging more than another, rather than equally, regardless of what they "see."
Nevermind, we're just going around in the same circles. You still ignore that substance of the argument and merely seek a word or phrase you think you can quibble about.
Your idea of an honest discussion is much different than mine.
I'm OUT.
One Brow said: "Each "sees" the other's clock as running slower in the twin paradox, but only one of those clocks actually *is* running slower, while the other is running faster."
Back to equivocation on the word "sees" (which I put in scare-quotes for a reason) by bringing the the doppler effect AND the relativistic effects. Let me put it another way: Each "sees" the other's clock as running slower and the other's distances as be foreshortened in the direction of motion.
You must mean "calculates". Why not just say calculate? You see what you see, and you calculate what you calculate. At relativistic distances, what you see is never what you calculate, due the relativity of simultaneity. So, if there is any equivocation here, it is by the person using "see" when they mean calculate.
Of course the question is not really even about what mistaken observers "see." It is about one aging more than another, rather than equally, regardless of what they "see."
In the twin paradox, each twin calcualtes the stationary twin will age more. Since you never see what you calculate anyhow, every observer is mistaken in that sense. This is one of the fundamental ideas in relativity.
Nevermind, we're just going around in the same circles. You still ignore that substance of the argument and merely seek a word or phrase you think you can quibble about.
The wiki article very clearly distinguished what a person sees and what they calculate. If you chose to deviate from that usage, and use one term to mean the other, is it really my fault that the result seems like equivocations or confusing?
You are totally incapable of assessing your own declarations for logical consistency, you merely re-shout your conclusons throughout eternity, logic be damned. NOTHING is ever inconsistent for you, because you simply ignore all inconsistencies and/or re-interpret all "facts" to conform to your prejudices. You do not confront issues, you sidestep them, attempt to quibble about irrelevancies, and thereafter ignore the substance of the issue. When confronted with a difficult question, something that would make people without an agenda at least think, you don't think for one second. You just re-shout your conclusion, presenting it as "fact." You will always pick sometime trivial to start a new argument about instead of ever really confronting the logical problems posed by your own assertions. In closing, I will just say a couple of things. Think about them sometime (heh, fat chance of that):
Just because Newton's bucket experiment involved rotational motion, you think it is ONLY ABOUT rotational motion. It aint, and that aint even the point. The point relates to profound issues such as the origin of inertia, absolute space, relative motion, etc., which have NOTHING to do with rotational motion per se.
Like the math guy said:
"The puzzling asymmetry of the spinning globes is essentially JUST ANOTHER FORM of the TWINS PARADOX, where the twins separate and re-converge (one accelerates away and back while the other remains stationary), and they end up with asymmetric lapses of proper time. How can the asymmetry be explained?"
He then quotes Al trying to give a Machian answer (later abandonded).
The other author makes it clear that:
"It should be clear by now that general relativity does not generalize the relativity
principle of special relativity from uniform to non-uniform motion....Einstein's theory also does not vindicate Mach's suggestion that
Newton's bucket experiment could be accountedfor in terms of relative motion
with respect to distant matter."
The issue here is about uniform versus accelerated motion and the EP. Without a Machian way to account for gravity (i.e., mass, not simply some posulated insistence that accelerated linear motion and gravity are equivalent) the "psuedo-fields" Al trumps up don't persuade anybody:
"The first condition is that it should be possible to ascribe the gravitational field
substituted for an object's acceleration on the basis of the equivalence principle to a MATERIAL SOURCE|anything from the object's immediate surroundings to the distant stars. Otherwise, acceleration with respect to absolute space would simply be replaced by the equally OBJECTIONABLE notion of fictitious gravitational fields."
archive.pitt.edu/archive/00004377/01/LoveMinusZero.pdf
You read the article, completely misunderstand it, declare that you FULLY understand it, and miss every essential point it makes. The easiest person in the world to convince is yourself, I guess. It don't take NUTHIN to do that. Of course you have been repeatedly presented with these very same points, from experts in the field, and done the same every time. You see nothing that you do not wish and choose to see. You seem to think that all it takes to "prove" your point is to shout down those with sense and inundate them with repeated assertions of any self-contradictory thought that pops into your head.
"archive.pitt.edu/archive/00004377/01/LoveMinusZero.pdf
According to Bondi, any notion of equivalence between inertial and accelerated observers is "physically meaningless" which goes to show how "void of of significance and general principle of relativity must be."
http://books.google.com/books?id=EY8KVI-05P0C&pg=PA196&lpg=PA196&dq=hermann+bondi+einstein+%22frank+discussion%22&source=bl&ots=SMtaOG0fxl&sig=M__JBZkJ2Td4f7Mwcw6VwJKVFdU&hl=en&ei=GpxPS7GDCIG4NvDsuIMJ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CAgQ6AEwAA#v=onepage&q=hermann%20bondi%20einstein%20%22frank%20discussion%22&f=false
You've lost me. You'd be better off to go tell "all other physicists" who agree with you how incompetent Bondi is, I spect.
I think I finally put together what might be your train of logic last night. Since you seldom take the time to delineate your process step-by-step, it can take a while. Is this really how you are thinking about things?
From your understanding of the twin paradox, the planetary twin is the real viewpoint. When you discuss the accelerated observer viewpoint, the gravitational forces that are used to to explain the movement of the planetary twin are not real, so they can't have any effect. That makes all the time-compression calculations from accelerated observer viewpoint fictional, the only real effects are movement effects. Since the ship twin sees the planetary twin as moving, the ship twin should calculate the planetary twin as being younger. The paradox is that the ship twin will be rong in this calculation.
On the other front, when Einstien moved past the development of SR to the development of GR, his initial goal was the complete relavitization of all motion, including all acceleration. He failed in this goal regarding acceleration, and this means that you can't ever treat acceration as a relative commodity.
Any of that not representative of what you have been saying?
One Brow said: "I think I finally put together what might be your train of logic last night. Since you seldom take the time to delineate your process step-by-step, it can take a while. Is this really how you are thinking about things?"
I've explained my points, in my own words, and those of numerous experts I've quoted, literally dozens of times.
One Brow said: "The paradox is that the ship twin will be rong in this calculation."
No, again, as I've been saying for about 1200 posts now, that is not the paradox.
I don't feel like going through it all again. If you really have any desire whatsoever to understand what I've been saying for weeks now, just scroll up.
One last hint: The first paragraph of wiki says: "In physics, the twin paradox is a thought experiment in special relativity, in which a twin makes a journey into space in a high-speed rocket and returns home to find he has aged less than his identical twin who stayed on Earth."
If not even a hypothethical postulation of which one is moving and which one is at rest is sufficient for a question about the hypothetical situation to have any "meaning" or be in any way determinable, then every reader should STOP, RIGHT THERE, and start shouting:
How wiki gone nuts!? It's impossible to know who is moving, this whole question is meaningless and preposterous! ALL MOTION IS RELATIVE, then can be no solution to this problem, because the whole suggestion that one is moving IS MEANINGLESS. It presumes ABSOLUTE MOTION (and, yeah, it does kinda presume absolute motion, in the end, I spoze).
Colton should have done the same with the wiki example (i.e., denounced it after reading the first sentence). You were very satisfied with this answer of his, because it repeated the same error you make repeatedly.
He said: "To answer the final question, “…will you be able to say that Pat will be younger than Chris from then on?” you must again specify the frame. I believe (see caveat above) that in frame 1/2, Pat will always be younger, and in frame 3 Chris will always be younger. You ask, “But which one is *really* younger?” (Sorry to put words in your mouth.) To see which is “really younger”, you would have to bring the two people into the same frame, next to each other."
In the problem he was addressing, like the wiki the problem, the person who had been accelerated had been ascertained by stipulation. But that's not sufficient to give a "real" answer with SR, it seems. Which leads one to conclude that SR predictions are utterly worthless. Even when the facts are "known," there can be no answer.
Even though the moving party has been determined, he still thinks that "reality" is dependent on the observer, and that neither can possibly be wrong until the stipulation has been empirically confirmed.
Such assessments ignore the very premises of the question, and pretend the premises don't exist, in order to inject an irrelvant philosophical claim, for philosophical purposes, evidently.
Question: IF clock a was accelerated to a speed of .86c relative to clock b, which clock would record less time, according to SR?
Answer: SR only says that the "if" part of your question can NEVER be ascertained, and therefore SR cannot, and does not even try to, answer such a question. The only "answer" is the assertion to even ask for an answer is meaningless. What SR predicts is that there is no answer; no more, no less. All questions, hypothetical or otherwise, about motion are strictly meaningless and unanswerable.
It appears the wiki article has now been re-worded, and now says:
"How the seeming contradiction is resolved, and how the absolute effect (one twin REALLY aging less) can result from a relative motion, can be explained within the standard framework of special relativity."
The orginallly has the word "really" in italics, not all caps, but that's the best I have.
This too should be enough for every devotee of philosophical relativism to IMMEDIATELY dismiss the whole wiki analysis as utterly unfounded and and simply WRONG.
NOBODY can use the word "really" when talking about the effects of motion, because nobody can ever know who is "really" moving, and SR makes no predictions whatsoever about what would happen, "really" or otherwise, to hear you tell it. And THIS part has to be utterly bogus, as you previously claimed: "The effect has been verified experimentally using precise measurements of clocks flown in airplanes." Another "meaningless" claim, no doubt.
One Brow said: "You must mean "calculates". Why not just say calculate? You see what you see, and you calculate what you calculate."
You still have it backwards. Without reference to the doppler effect, wiki says this:
"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."
This is what they "see." They can use their knowledge of the doppler effect COMBINED WITH their personal knowledge about their absolute relative speed to "calculate" an answer that is DIFFERENT FROM what they "see," however. Once wiki brings in the "doppler + SR" combo, it says this:
"To avoid confusion, note the distinction between what each twin sees, and what each would calculate...And he does not confuse the rate at which the image is aging with the rate at which his twin was aging when the image was transmitted."
Just another case where you got things all confused and told me that reading it the right way, for what it actually says, was proof that I knew absolutely nothing about SR.
I've explained my points, in my own words, and those of numerous experts I've quoted, literally dozens of times.
What you don't do is offer the trains of logic that lead to these conclusions, at least not regularly.
ALL MOTION IS RELATIVE, then can be no solution to this problem,
See, again you make another huge jump in your logic. Even if all motion were relative, why should all motion being relative mean there is no solution?
In the problem he was addressing, like the wiki the problem, the person who had been accelerated had been ascertained by stipulation. But that's not sufficient to give a "real" answer with SR, it seems. Which leads one to conclude that SR predictions are utterly worthless. Even when the facts are "known," there can be no answer.
I've already given you the only possible answer of the type you seek: Pat and Chris are always the same age, as long as both stay in an inertial environment.
Here's another way to see that: find a frame Q which so the time it takes for light to Pat to Q is always the same as the time it takes for light to travel from Chris to Q. Q can see who clock is really moving faster, right? Q has to stay half-way between Pat and Chris. That means, if Pat is moving at a speed of .6c relative to Chris, Q will be moving at a speed of .3c relative to both Pat and Chris. So, Q will see the exact same time dilation in Pat and Chris.
Even though the moving party has been determined, he still thinks that "reality" is dependent on the observer, and that neither can possibly be wrong until the stipulation has been empirically confirmed.
I think you just don't like the description of reality offered.
Question: IF clock a was accelerated to a speed of .86c relative to clock b, which clock would record less time, according to SR?
Answer: SR only says that the "if" part of your question can NEVER be ascertained, and therefore SR cannot, and does not even try to, answer such a question.
Assuming that "acceleration" means "change in inertia", and "inertia" is "motion at uniform speed in a straight line", then for SR the question is incomplete. If you give an incomplete questions, you get an incomplete answer. What's missing is the nature of the acceleration of a, and the statis of clock b: is either following or leaving a geodeisic in their acceleration/statis, and to what degree. If you ask an incomplete question, of course you get an incomplete answer.
The only "answer" is the assertion to even ask for an answer is meaningless. What SR predicts is that there is no answer; no more, no less. All questions, hypothetical or otherwise, about motion are strictly meaningless and unanswerable.
Complete questions can be answered.
... SR makes no predictions whatsoever about what would happen, "really" or otherwise, to hear you tell it.
Perhaps you should listen more carefully, then, or at least explain your logical leap above.
You still have it backwards. Without reference to the doppler effect, wiki says this:
"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."
This describes the outbound journey only. On the return leg, the shipboard twin sees something different. "the Earth twin sees the ship twin age by the same amount in the red and blue shifted images; the ship twin sees the Earth twin age by different amounts in the red and blue shifted images."
This is what they "see." They can use their knowledge of the doppler effect COMBINED WITH their personal knowledge about their absolute relative speed to "calculate" an answer that is DIFFERENT FROM what they "see," however. Once wiki brings in the "doppler + SR" combo, it says this:
"To avoid confusion, note the distinction between what each twin sees, and what each would calculate...And he does not confuse the rate at which the image is aging with the rate at which his twin was aging when the image was transmitted."
In other words, the ship twin is aware that the earth twin is not really aging at different rates on the outbound and inbound legs of the journey, despite appearances.
Just another case where you got things all confused and told me that reading it the right way, for what it actually says, was proof that I knew absolutely nothing about SR.
You are offering little to change that evaluation.
As always, you miss the point of(or deliberately miscontrue) everything said to you. How convenient, eh? Bye.
One Brow said: "I've already given you the only possible answer of the type you seek: Pat and Chris are always the same age, as long as both stay in an inertial environment."
No one can "see" that by the example you gave. This is NOT even a question of how a, b, c, d, or e, will "see" it. It is a matter of what SR predicts, without regard to who sees what.
As I have already pointed out: SR predicts asymmetry with differing relative speeds it does NOT predict that "Pat and Chris are always the same age, as long as both stay in an inertial environment."
The wiki example clearly illustrates this. The travelling twin would NOT age 4 fewer years (or whatever it was) if he simply made a one day journey. He ages less each and every hour. The longer he travels, the greater the final accumulated age difference. This all happens EVEN THOUGH, like P & C, they "stay in the same inertial enviroment" for the vast majority of that time (turn-around excepted, but not takeoff, because wiki treats that as instanteous). Same with a GPS satellite orbiting earth.
All of this within straight SR predictions, no surprises. SR does NOT predict equal aging for all in the "same interial frame." As pointed out repeatedly, the aging is asymmetrical, depending on who has been previously accelerated with respect to the other. But, of course, that's the whole problem. I have pointed all of this out already, very recently and repeatedly throughout this thread, without a word of acknowledgement or rebuttal from you. You merely reassert your previous statement.
The "only possible answer" you arrive at has nothing to do with what SR predicts. It is merely the expression of what you deduce from your metaphysics. You will obviously never see that.
If you need to go, you do.
As far as I can tell, your point is if "ALL MOTION IS RELATIVE, then can be no solution to this problem". You can't justify this statement, because it's not true.
It is a matter of what SR predicts, without regard to who sees what.
It's also a matter of what can exist.
As I have already pointed out: SR predicts asymmetry with differing relative speeds
Absolutely. If they have different speds relative to a third party, they will age differently.
it does NOT predict that "Pat and Chris are always the same age, as long as both stay in an inertial environment."
Since both Pat and Chris follow the geodeisic, this is exactly what it predicts.
One Brow said: "As far as I can tell, your point is if "ALL MOTION IS RELATIVE, then can be no solution to this problem". You can't justify this statement, because it's not true."
Of course it isn't. It's strictly satire/sarcasm, based on the positions you have taken (very selectively) throughout this thread.
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As always, you just deny and reassert your position:
"Absolutely. If they have different speds relative to a third party, they will age differently."
Third parties have nothing to do with what SR predicts, as has been made quite clear by Al, wiki, and everyone else. Your philosophical position thinks they do, but not SR. Whatever the two twins in the wiki see or think they see, the answer is the same, and there is no "third party" to it.
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I said: "it does NOT predict that "Pat and Chris are always the same age, as long as both stay in an inertial environment."
One Brow said: "Since both Pat and Chris follow the geodeisic, this is exactly what it predicts."
Cite me one authority saying this is so. "The geodesic?" Is there only one in the universe? P & C are both moving uniformly (inertially) but they are NOT maintaining the same distance from each other. They are constantly getting farther apart. Which is just a long-ass way of saying that they are moving with respect to each other. What the hell is "THE geodesic" here?
Your statement is senseless, and you have already very recently contradicted yourself with this type of claim in the GPS context (which I asked about and you ignored, of course). Can you do ANYTHING other than make assertions about things you don't even understand? I notice you didn't respond to a word of my explanation, as always. On second thought ,forget citing or explaining anything, just shout it another 14,256 times, eh? That's what you are good at.
SR: As an object approaches the speed of light, it's mass increases. The closer it gets to the speed of light, the more it's mass will increase and, at the speed of light, it mass would be infinite:
1. Is this claimed deemed to be true by SR?
2. If so, is it only true if a second or third party sees it?
3. Does it all become false, which no increase in mass whatsoever, if a traveller doesn't "think" he is moving?
Does the prediction change if an observer has no way of knowing how fast the object is moving. Does SR predict that, in the case of the existence of an ignorant observer, all the laws of SR change? Like, in that case, mass is neither increasing nor decreasing, sumthin like that?
I don't think so! Homey don't play dat.
Feel free to substitute the concept of "time slowing down" for "mass" in that series of posts.
"if all motion is relative, then can be no solution to this problem. You can't justify this statement, because it's not true."
Of course it isn't. It's strictly satire/sarcasm, based on the positions you have taken (very selectively) throughout this thread.
Then, you agree you can reseolve the twin paradox even though all the described motion in it is relative?
"Absolutely. If they have different speds relative to a third party, they will age differently."
Third parties have nothing to do with what SR predicts, as has been made quite clear by Al, wiki, and everyone else.
It is the thrid party who see them age differently (except for a very small selection of viewpoints). You can't discuss whether they age differently or not without discussing for whom they may be aging differently, except in a highly abstract way that ignores teh relativity of simultaneity. In that highly abstract way, Pat and Chris always age at the same rate.
Your philosophical position thinks they do, but not SR. Whatever the two twins in the wiki see or think they see, the answer is the same, and there is no "third party" to it.
In the twin paradox, the twins begin and end following the same geodeisic (in flat space, this would mean at the same place, at the same time, with the same speed and direction). The traveling twin changes the geodeisic that he follows at least three times in between. So yes, any observer of that situation can see there is a time difference. SR predicts the difference.
With Pat/Chris, the twins are following geodeisics with widely variant directions and a high speed between them. SR says that it is meaningless to compare them in the exact same way you can the twins. You can compare them based upon what an observer sees, and every observer on a different geodeisic from the twins will see something different, or you can compare them by ignoring the relativity of simultaneity. If you do that, Pat and Chris age at the same rate.
AintNoThang: "it does NOT predict that "Pat and Chris are always the same age, as long as both stay in an inertial environment."
One Brow said: "Since both Pat and Chris follow the geodeisic, this is exactly what it predicts."
Cite me one authority saying this is so.
colton said: It can be proven (I think I did in a class, once) that when two objects start and end at the same point in space-time (same position at the same time), if one object follows a geodesic, it will always have the greater “proper time” (time elapsed for the object).
"The geodesic?" Is there only one in the universe?
In flat space, there is one for every direction from every point. In curved space, there is one for every direction at every speed through every point.
P & C are both moving uniformly (inertially) but they are NOT maintaining the same distance from each other. They are constantly getting farther apart. Which is just a long-ass way of saying that they are moving with respect to each other. What the hell is "THE geodesic" here?
Each follows the geodeisic for it's respective place and inertia. If you prefer, "following a geodeisic".
Your statement is senseless, and you have already very recently contradicted yourself with this type of claim in the GPS context (which I asked about and you ignored, of course).
How so? GPS satellites follow a geodeisic, and their time elasped is maximal.
I notice you didn't respond to a word of my explanation, as always.
When I respond to everything you say, the discussions seem to get confused. So, I have been trying to respond only to the points that I see as the core errors.
SR: As an object approaches the speed of light, it's mass increases. The closer it gets to the speed of light, the more it's mass will increase
No object can approach the speed of light. No matter how you are traveling, the speed of light in a vacuum is always c. No matter what you do, it will never be more than c or less than c.
Now, here's my dilemma: this is a very basic error on your part, and you goon to ask a lot of questions assuming this to be true. If I don't answer your questions, you will accuse me of dodging them. If I do answer them, you will think my answers are nonesense, based on this core misunderstanding. Either way, you have accused me of answering dishonestly in similar situations.
That said, there is one way you can seem to approach the speed of light: in the eyes of another observer. That observer can see you getting closer to the speed of light. You will never see yourself that way.
and, at the speed of light, it mass would be infinite
No one knows what would happen if one could actually accelerate mass to the speed of light somehow. "The mass becomes infinite" is a technical shortcut for "if you choose any value M that you want the given mass to exceed, you can find some speed v relative to you where the mass of the object exceeds M".
:1. Is this claimed deemed to be true by SR?
Not as you have described it.
2. If so, is it only true if a second or third party sees it?
It is a description of what a second or third party sees.
3. Does it all become false, which no increase in mass whatsoever, if a traveller doesn't "think" he is moving?
The traveller sees no increase in mass, regardless of what he thinks.
Let me offer you an example. Let's say to exert the gravitational effects of a black hole, you need 100 solar masses. You can put a dime on a rocket, or whatever, and accelerate it to some speed, maybe (1-10^-100)*c (that would be a hundred nines in the .99...9c) relative to you, where you now see the dime weighing 200+ solar masses. The dime will not behave like a black hole. Inside the rocket cabin, the dime will not create an event horizon, etc.
Does the prediction change if an observer has no way of knowing how fast the object is moving.
no.
Does SR predict that, in the case of the existence of an ignorant observer, all the laws of SR change?
No.
Like, in that case, mass is neither increasing nor decreasing, sumthin like that?
No. Any knowledge about who is traveling, or how fast, does not affect what the third party sees.
Feel free to substitute the concept of "time slowing down" for "mass" in that series of posts.
Same thing.
One Brow said: "No object can approach the speed of light."
More irrelevant quibbling, and completely fallacious at that. If I increase my speed from 1 mile per century to 2 miles per century, I am "approaching" (getting closer to) the speed of light.
One Brow said: "colton said: It can be proven (I think I did in a class, once) that when two objects start and end at the same point in space-time (same position at the same time), if one object follows a geodesic, it will always have the greater “proper time” (time elapsed for the object)."
And from that statement of Colton's, you get this!?: "[SR predicts that] Pat and Chris are always the same age, as long as both stay in an inertial environment."
Heh, even a cursory examination for consistency should immediately tell you your conclusion is incorrect. Any other "authorities" for your repeated assertion?
One Brow said: "Then, you agree you can reseolve the twin paradox even though all the described motion in it is relative?"
1. You still don't know what the "paradox" is.
2. What do you even mean by this?: "all the described motion in it is relative?" What of significance do you even think you are saying?
The acceleration in the wiki problem is absolute, with the result that the travelling twin's speed is absolutely greater than that of the stay at home twin. This is not relative, and it is precisely that which allows you to arrive at a "real" aging difference between the two twins.
There is NO paradox within SR itself. The "paradox" only arises when people like yourself try to engraft a misguided philosophical postion onto SR, i.e., that "all motion is relative." If all motion were truly "relative" (relational) there would be NO absolute age difference between the two, any and all "appearances" to the contrary notwithstanding (which is what you erroneously try to claim for Pat and Chris--that SR predicts they age will "the same").
SR explains how, when two objects are moving relative to the other, each observer (if he assumes that he is at rest, and not the other) will also "assume" that the other's clock is running slower.
But it does NOT predict that both clock really will be running slower. Nor does it predict that they will always be running the same.
SR does not require any observers whatsover to make it's prediction.
I said: "SR explains how, when two objects are moving relative to the other, each observer (if he assumes that he is at rest, and not the other) will also "assume" that the other's clock is running slower."
Conversely, when both observers agree on the true motion (as in the wiki example where all parties agree that it is the space twin who has been accelerated and is moving faster), NEITHER will think that only "the other's" clock is running slower. Both will "know" that the space twin's clock is running slower, not the earth twin's. All thanks to the observer-independent predictions of SR, of course.
You have been totally unable to disabuse your self of such mistaken notions as:
1. SR predictions depend on what a particular observer sees or thinks
2. If two or more observers can assess motion from different standpoints, that, in and of itself, makes motion "relative."
A third implicit mistake you have been making (and Colton, to the extent I have already noted--did he ever respond to my questions, btw) is that no SR prediction is "valid" unless and until the particular circumstances have been empirically confirmed. Knowledge and/or confirmation of the facts has NOTHING to do with the prediction itself.
As I said before, in the wiki example, the space twin is aging at a slower rate whether you, looking up into the sky and seeing the twin's ship, know it's state of motion or not. The prediction stems from the motion itself, not your knowledge of it. It's not that there "is no answer" or "is no reality" until you personally become aware of it.
Suppose I make prediction that if there is a hard rain my driveway will get wet. Suppose I confuse myself with invalid logic and hence predict to you that if the driveway is wet, that proves there has been a hard rain.
To show me how stupid I am, you go out and wet the driveway with a garden hose, and declare: "See, your stupid-ass prediction was wrong."
Your proof that my prediction was invalid did NOT change my prediction. It simply disproved it. The prediction itself is independent of any confirmation whether it is a valid prediction, or not.
You and Colton have effectively been denying that SR predictions are valid. You both evidently subscribe to a purely relational theory of motion. Perhaps one or both of you can elaborate on exactly how your particular theory of motion works, eh?
I quoted Bondi and Synge to you, one of whom bemoaned that it was now too late to change the convention of calling it Einstein's "theory of general relativity" instead of Einstien's "theory of gravity."
For what it's worth, Einstien himself later said he regretted using that terminology, stating that he should have called it the "general theory of invariance" (or something like that).
One Brow said: "No object can approach the speed of light."
More irrelevant quibbling, and completely fallacious at that. If I increase my speed from 1 mile per century to 2 miles per century, I am "approaching" (getting closer to) the speed of light.
At one mile per century (compared to some rest frame), the speed difference between you and light in your rest frame is c. At one mile per millisecond (compared to some other rest frame), the the speed difference between you and light is c in your rest frame. You never aproach the speed of light.
One Brow said: "colton said: It can be proven (I think I did in a class, once) that when two objects start and end at the same point in space-time (same position at the same time), if one object follows a geodesic, it will always have the greater “proper time” (time elapsed for the object)."
And from that statement of Colton's, you get this!?: "[SR predicts that] Pat and Chris are always the same age, as long as both stay in an inertial environment."
Heh, even a cursory examination for consistency should immediately tell you your conclusion is incorrect. Any other "authorities" for your repeated assertion?
That's logic you should be able to follow. In the flat space of Pat and Chris, geodeisics are inertial paths. Any object following a geodeisic will experience the maximal proper time. Therefore, Pat and Chris experience the same amount of time passing. You can also see this from the fact that, for any observer that has the same light-delay between Pat and Chris (and therefore sees them when they are at the same point in time), Pat and Chris age the same.
One Brow said: "Then, you agree you can reseolve the twin paradox even though all the described motion in it is relative?"
1. You still don't know what the "paradox" is.
I am using the wiki's description of the paradox as the arising of an absolute time difference from relative motion.
2. What do you even mean by this?: "all the described motion in it is relative?" What of significance do you even think you are saying?
The acceleration in the wiki problem is absolute, with the result that the travelling twin's speed is absolutely greater than that of the stay at home twin. This is not relative, and it is precisely that which allows you to arrive at a "real" aging difference between the two twins.
Feel free to persist in this delusion. The absolute in the problem is the deviaiton of the ship twin from a geodeisic path, while the earth twin follows a geodeisic. This is true in both the K and the K' interpretations of the event, so it is the absolute.
There is NO paradox within SR itself. The "paradox" only arises when people like yourself try to engraft a misguided philosophical postion onto SR, i.e., that "all motion is relative." If all motion were truly "relative" (relational) there would be NO absolute age difference between the two, any and all "appearances" to the contrary notwithstanding (which is what you erroneously try to claim for Pat and Chris--that SR predicts they age will "the same").
Here is one of the main errors you make. Motion being relative in a specific scenario does not mean that every type of motion is identical, or even that every state of not moving is identical. Even though the motion of the twin paradox is relative, the movement of U2 (the ship clock) in K is not the same as the movement of U1 (the earth clock) in K'. The non-motion of U1 in K is also fundamentally different from the non-motion of U2 in K'. As long as you keep ignoring, overlooking, and/or misunderstanding this point, you will be missing a vital piece to seeing what is happening. I think you're smart enough to get this.
SR explains how, when two objects are moving relative to the other, each observer (if he assumes that he is at rest, and not the other) will also "assume" that the other's clock is running slower.
By "assume", I take it you mean each will calculate that.
But it does NOT predict that both clock really will be running slower.
Each slower than the other? I agree, it does not.
Nor does it predict that they will always be running the same.
If both observers are following geodeisics, that is exactly what it predicts.
SR does not require any observers whatsover to make it's prediction.
I agree. It only requires requires rest frames from which observations can be made, as does any other theory of the physics of motion.
I said: "SR explains how, when two objects are moving relative to the other, each observer (if he assumes that he is at rest, and not the other) will also "assume" that the other's clock is running slower."
Conversely, when both observers agree on the true motion (as in the wiki example where all parties agree that it is the space twin who has been accelerated and is moving faster), NEITHER will think that only "the other's" clock is running slower. Both will "know" that the space twin's clock is running slower, not the earth twin's. All thanks to the observer-independent predictions of SR, of course.
In the twin paradox, both twins know that the earth twins non-motion/motion is fundamentally different from the ship twin's motion/non-motion.
You have been totally unable to disabuse your self of such mistaken notions as:
1. SR predictions depend on what a particular observer sees or thinks
2. If two or more observers can assess motion from different standpoints, that, in and of itself, makes motion "relative."
I am unable to disabuse myself of notions that I don't believe in?
A third implicit mistake you have been making (and Colton, to the extent I have already noted--did he ever respond to my questions, btw) is that no SR prediction is "valid" unless and until the particular circumstances have been empirically confirmed.
Another notion I don't accept.
As I said before, in the wiki example, the space twin is aging at a slower rate whether you, looking up into the sky and seeing the twin's ship, know it's state of motion or not.
I have agreed with you on this before.
The prediction stems from the motion itself, not your knowledge of it. It's not that there "is no answer" or "is no reality" until you personally become aware of it.
Agreed.
You and Colton have effectively been denying that SR predictions are valid.
Frankly, you don't understand SR well enough to evaluate that.
You both evidently subscribe to a purely relational theory of motion. Perhaps one or both of you can elaborate on exactly how your particular theory of motion works, eh?
You want something explained further than the wiki pages do? Different?
I quoted Bondi and Synge to you, one of whom bemoaned that it was now too late to change the convention of calling it Einstein's "theory of general relativity" instead of Einstien's "theory of gravity."
For what it's worth, Einstien himself later said he regretted using that terminology, stating that he should have called it the "general theory of invariance" (or something like that).
Calling it a "general theory of invariance" does not rememdy the defect of "general theory of relativity", because it would still not be truly general.
One Brow said: "That's logic you should be able to follow."
What "logic?" As always you merely reassert your conclusion, without more: "In the flat space of Pat and Chris, geodeisics are inertial paths. Any object following a geodeisic will experience the maximal proper time. Therefore..."
That's one unfortunate thing about this whole thread: You think that restating your unsupported conclusions 1,000,000 times is an exercise in "logic."
If your supposed "logic" has to do with "light delay," or your re-assertion for the need of "third observers," where's the relevance?
What "logic?" As always you merely reassert your conclusion,
Sorry, I'll lay it out for you better. The starting points:
P1. Pat is following a geodeisic.
P2. Chris is following a geodeisic.
P3. 'when two objects start and end at the same point in space-time (same position at the same time), if one object follows a geodesic, it will always have the greater “proper time” (time elapsed for the object).'
P4. If an object experiences as much or more proper time passing than any other object, it is experiencing the maximal proper time passed.
The logical flow:
S1. Pat will experience as much or more proper time than any other object (P1 & P3)
S2. Pat experiences the maximal amount of propert time (S1 & P4).
S3. The amount of time experienced by Chris is less than or equal to the amount of time experienced by Pat (Definition of maximal in S2).
S4. Chris will experience as much or more proper time than any other object (P2 & P3)
S5. Chris experiences the maximal amount of propert time (S4 & P4).
S6. The amount of time experienced by Pat is less than or equal to the amount of time experienced by Chris (Definition of maximalin S5).
S7. The amount of time experienced by Pat is equal to the amount of time experienced by Chris.
(antisymmetric property on S3 and S6).
One Brow said:
"Feel free to persist in this delusion. The absolute in the problem is the deviaiton of the ship twin from a geodeisic path, while the earth twin follows a geodeisic. This is true in both the K and the K' interpretations of the event, so it is the absolute."
Heh, who's deluded here?
1. Deivation from the geodesic simply means "acceleration." As I said, the acceleration is absolute. It follows that the increase in speed is absolute in this example.
2. K and K'? As author after author has said, this is strictly an SR problem? Are you referring to Einstein's claimed "resolution?" This problem has NOTHING to do with gravitational fields. To the extent it does (and it doesn't) Einstien does NOT eliminate the asymmetry in any event. Of course, the fantastical assumptions in his "resolution" seem to be almost universally rejected these days anyway, for obvious reasons which you apparently still do not understand, despite numerous caveats from experts.
You have a new magic word, replacing "inherently relative," i.e. "geodesic," which you now seem to think magically ratifies all of your misunderstandings. Help yourself.
Reading further in your post, I see that you are in fact relying on "gravitional" time distortion to try to unsucessfully "resolve" an SR problem (which excludes gravity). This whole thread has been about "kinematic" dilation (due to speed) not gravitational add-ins, until you tried to change course. GR is irrelvant. I have already told you, many times, why it does NOTHING to change the predictions of SR regarding KINEMATIC time dilation.
One Brow said: "If both observers are following geodeisics, that is exactly what it predicts."
Say it a million more times. Then find an authoritative source to support your whimsical asssertions.
One Brow said: "P3. 'when two objects start and end at the same point in space-time (same position at the same time), if one objects follows a geodesic, it will always have the greater “proper time” (time elapsed for the object)."
I agree with this, that's basically the definition of a geodesic. But it only pertains to two object which both start and end at the same place. It says nothing object other objects in the universe, one way, or the other.
One Brow said: "P4. If an object experiences as much or more proper time passing than any other object, it is experiencing the maximal proper time passed."
What do you mean "any other object?" Any other object in the universe? If it is ever discovered that one particular object experiences more time than any other, then a universal reference frame will indeed have been established. Everything else will be accelerated relative to it.
I can even fathom what you are saying beyond that, unless you make it clear what you are saying. You are treating what happens in a very particular circumstance as though it is universal regardless of circumstance. Are you claiming that any two objects which have never both (1) been at the same place, and then subsequently (2) returned to that same place MUST be the same age, all experience identical clock rates so long as they are both inertial (geodesic)? That does not even begin to follow, and contradicts SR.
Suppose I say: If a guy falls off a ladder he will hit the ground.
Would you take that to imply that if he fell off a building he would not hit the ground, because a building is not a ladder? Apparently you would.
I'm back to the point where I can only recommend that you discuss your novel theories with Colton.
One Brow said: "In the twin paradox, both twins know that the earth twins non-motion/motion is fundamentally different from the ship twin's motion/non-motion."
Yeah, exactly. Do you have a point? Is this supposed to refute, rather than ratify, what I just said?
Read about it anywhere on the net:
Kinematic time distortion (SR) is a separate and distinction notion and prediction from distortion due to gravity (GR). Their causes are distinct, and you can always have one without the other. A point made clear in the GPS discussions A point I made again hundreds of posts ago. Something you apparently still don't understand.
If a distant star is in my inertial frame (not moving relative to me) and if it sends "light signgals" to me 10 seconds apart, then I will eventually recieve them 10 seconds apart (although I may not recieve the first one for many years). It is not accelerating with respect to me, or me to it. Big deal. We are moving, if at all, at the same speed.
That is, of course, a completely different situation from one where the star is constantly getting nearer to, or further from, me. It is, needless to say, completely different from the Pat and Chris scenario also.
You have apparently somehow confused the two situations. If Pat and Chris merely hovered, without any change in distance from each other, then, indeed, time would be the same for both of them. Otherwise, no it WOULDN'T be, if you believe SR (and GR).
I said: "Otherwise, no it WOULDN'T be, if you believe SR (and GR)."
And, of course, that's true EVEN IF both are inertial (i.e., for SR purposes, moving at a uniform speed in a straight line with no external forces acting upon them. And of course, saying this is equivalent to saying: "...that's true EVEN IF both are both are "on a geodesic."
"Feel free to persist in this delusion. The absolute in the problem is the deviaiton of the ship twin from a geodeisic path, while the earth twin follows a geodeisic. This is true in both the K and the K' interpretations of the event, so it is the absolute."
Heh, who's deluded here?
That would be you.
1. Deivation from the geodesic simply means "acceleration."
Previously, acceleration has meant a change in inertia movement, with inertia being defined as movement in a straight line at a constant speed (relative to something else). Under that definition, one can deviate from a geodeisic without accelerating (as the ship does in K'), and one can accelerate along a geodeisic (as any saltellite in orbit does). They are different things.
As I said, the acceleration is absolute. It follows that the increase in speed is absolute in this example.
Repeating this does not make it true.
2. K and K'? As author after author has said, this is strictly an SR problem?
K' is an SR viewpoint with an observer that leaves the geodeisic.
Are you referring to Einstein's claimed "resolution?" This problem has NOTHING to do with gravitational fields. To the extent it does (and it doesn't) Einstien does NOT eliminate the asymmetry in any event.
That's what I just told you.
Of course, the fantastical assumptions in his "resolution" seem to be almost universally rejected these days anyway, for obvious reasons which you apparently still do not understand, despite numerous caveats from experts.
What assumptions did Einstein make that are specifically rejected? You don't actually think Einstien thought there would be real gravitational fields, do you?
You have a new magic word, replacing "inherently relative," i.e. "geodesic," which you now seem to think magically ratifies all of your misunderstandings. Help yourself.
It's a word you obviously don't uncerstand or care to understand, but it is not a magic word. It is a standard term in physics, and relativity thoery specifically.
Reading further in your post, I see that you are in fact relying on "gravitional" time distortion to try to unsucessfully "resolve" an SR problem (which excludes gravity). This whole thread has been about "kinematic" dilation (due to speed) not gravitational add-ins, until you tried to change course. GR is irrelvant. I have already told you, many times, why it does NOTHING to change the predictions of SR regarding KINEMATIC time dilation.
Simply repeating that there is a great kinematic/gravitational distinction does not make it true.
One Brow said: "If both observers are following geodeisics, that is exactly what it predicts."
Say it a million more times. Then find an authoritative source to support your whimsical asssertions.
colton already did. It's your turn. Find an actual physicist that disagrees, and we can play dueling experts. That way you will save yourself from actually having to learn this.
One Brow said: "P3. 'when two objects start and end at the same point in space-time (same position at the same time), if one objects follows a geodesic, it will always have the greater “proper time” (time elapsed for the object)."
I agree with this, that's basically the definition of a geodesic. But it only pertains to two object which both start and end at the same place. It says nothing object other objects in the universe, one way, or the other.
So, you agree that Pat experiences maximal time compared to any other object that would start and end in his rest frame, and that Chris does as well? Describe how one could then experience more time thant the other. What does that mean, in light of this observation?
One Brow said: "P4. If an object experiences as much or more proper time passing than any other object, it is experiencing the maximal proper time passed."
What do you mean "any other object?" Any other object in the universe? If it is ever discovered that one particular object experiences more time than any other, then a universal reference frame will indeed have been established. Everything else will be accelerated relative to it.
The phrase used was "as much or more".
I can even fathom what you are saying beyond that, unless you make it clear what you are saying. You are treating what happens in a very particular circumstance as though it is universal regardless of circumstance. Are you claiming that any two objects which have never both (1) been at the same place, and then subsequently (2) returned to that same place MUST be the same age, all experience identical clock rates so long as they are both inertial (geodesic)? That does not even begin to follow, and contradicts SR.
Actually, that is a consequence of SR, not a contradiction of it.
Suppose I say: If a guy falls off a ladder he will hit the ground.
Would you take that to imply that if he fell off a building he would not hit the ground, because a building is not a ladder? Apparently you would.
If you think the argument is about how things are named, you have misunderstood it.
I'm back to the point where I can only recommend that you discuss your novel theories with Colton.
You mean get him to agree with me some more?
One Brow said: "In the twin paradox, both twins know that the earth twins non-motion/motion is fundamentally different from the ship twin's motion/non-motion."
Yeah, exactly. Do you have a point? Is this supposed to refute, rather than ratify, what I just said?
It shows that your parody of my position is completely off-kilter, at the very least. It shows that the K' analysis of the scenario can't be considered less valid than K because the motion is not relative, or the acceleration is absolute, or some such thing.
Kinematic time distortion (SR) is a separate and distinction notion and prediction from distortion due to gravity (GR).
In the GR equations, the same equations and positions in the tensors can produce both the "kinematic" and the "gravitational" effects. They are the same effects. In practice, we choose a rest frame that will make the GR equations as simple as possible. This often means that equations will simplify to the point where some equations will disappear, and one or two will describe each effect. The most preferred frames are those that preserve the conservation of energy, and they often coincide the easiest frames to use. However, the conservation of energy is not a concept within relativity theory, it's an add-on to make our choice seem less arbitrary.
Their causes are distinct, and you can always have one without the other. A point made clear in the GPS discussions A point I made again hundreds of posts ago. Something you apparently still don't understand.
I understand that you want to say there is some major, unbridgeable distinction between kinetic and gravitational effects on time. I understand that you feel the preference of physicists for frames of reference that preserve the conservation of energy carries with it an implied condemnation of other frames of reference. I understand that you think any explanations that deviate from those frames fanciful, pointless speculation with no meaning. So, what do you really think I don't understand about your position, as opposed to just don't agree with?
If a distant star is in my inertial frame (not moving relative to me) and if it sends "light signgals" to me 10 seconds apart, then I will eventually recieve them 10 seconds apart (although I may not recieve the first one for many years). It is not accelerating with respect to me, or me to it. Big deal. We are moving, if at all, at the same speed.
That is, of course, a completely different situation from one where the star is constantly getting nearer to, or further from, me. It is, needless to say, completely different from the Pat and Chris scenario also.
Of course. It is different from Pat/Chris. Did you have a point?
You have apparently somehow confused the two situations. If Pat and Chris merely hovered, without any change in distance from each other, then, indeed, time would be the same for both of them.
Of course.
Otherwise, no it WOULDN'T be, if you believe SR (and GR).
You are incorrect. SR/GR says that, to the degree the statement makes sense at all without establishing a rest frame, time passes at the same rate for both Pat and Chris at long as both stay in geodeisics.
By the same token, you don't need a "third person" to determine if two objects are moving with respect to each other. Either the two objects are maintaining the same distance from each other (in which case they aint movin, relative to each other) or they aint, in which case at least one of them if "really" moving.
One Brow said: "Under that definition, one can deviate from a geodeisic without accelerating (as the ship does in K')"
Jesus H. Christ. We went through this at length, and finally had to "ask Colton." Both clocks are accelerating in K'. Einstein himself says the one "moving" is "accelerating." The other, though not moving, is accelerating by virtue of external forces acting on it (including, but not limited to, gravity).
It does no good. You always pop back up to reassert the same positions you were forced to abandon. Deviation from a geodesic is acceleration, Non-deviation is inertial, under GR. Again, the problem is even about GR to begin with. It is impossible to reason with you. You never hear or remember a word.
One Brow said: "K' is an SR viewpoint with an observer that leaves the geodeisic."
Newsflash: Special relativity does NOT address issues of gravity. That is why the "general" theory was developed. Well, one reason, anyway, another being Einstein's determination to try to "relativize" acceleration.
A couple of things for you to consider (fat chance).
1. You want to rely on the EP, which tries to say gravitation IS acceleration.
2. Gravitation, on its own, does NOT produce a uniform speed or a uniform velocity. It produce CONSTANT (ever-increasing) acceleration. If left to the accelerative aspects of gravitation alone, one would soon exceed the speed of light (unless he "changed direction" due to external influences). This might be a massive planet.
One Brow said: "colton already did. It's your turn. Find an actual physicist that disagrees, and we can play dueling experts. That way you will save yourself from actually having to learn this."
Colton said no such thing. Ask him if all objects in the universe which are "on a geodesic" all experience the exact same local time. If he says "yes," ask him if he believes SR is completely false.
One Brow said: "You mean get him to agree with me some more?"
No, I mean let him say things that contradict you so that you can then tell yourself that he agrees with you.
One Brow said: "You are incorrect. SR/GR says that, to the degree the statement makes sense at all without establishing a rest frame, time passes at the same rate for both Pat and Chris at long as both stay in geodeisics."
Say it again, fool. Then, think about it sometime. Heh, fat chance. You have presented no arguments to support your conclusion, nor do you intend to. You will just keep asserting it, with or without consistent reasons. For you, your undisclosed (to you) philosophical assertion are simple fact, and no amount of real facts could ever convince you otherwise.
I give up.
One Brow said: "I understand that you want to say there is some major, unbridgeable distinction between kinetic and gravitational effects on time."
I don't necessarily "want to say" any such thing. Relativity both special and general, could be complete bullshit, for all I know.
SR says that time dilates with speed IN ORDER TO claim that the speed of light will always appear to be the same to all observerss.
GR posits gravitational time distortion as a separate and distinct phenomenon. If you want to deny it, take it up with the relativists, eh? I'm simply assuming their premises, for the sake of this discussion.
If you think relativity is completely bogus, as your conclusions clearly suggest, then please feel free to say so.
One Brow said: "Describe how one could then experience more time thant the other. What does that mean, in light of this observation?"
"This observation" is irrelevant. SR, not me, "describes" how one could then experience more time than another:
"One of the fundamental results of Albert Einstein's special theory of relativity is a phenomenon known as time dilation. Simply put, this result states that time moves more slowly for a moving object than it does for an object at rest."
Take object A, and call it "at rest." Then take object B which is separating from A at the rate of one mile per hour. Object B is now "moving" with respect to A, and consequently times move more slowly for B than A.
Now take object C, which is separating from A at the rate of 2 miles per hour (and from B at 1 mph). Time for C will be less than for both B and A.
Note that, at this point, you could just ignore A and simply say that C is moving relative to B.
Take objects D, E, F, G, etc., ad infinitum. Progressively add 1 mph, or any fraction thereof, to the rate of its separation from A.
You can end up with an infinite number of objects all moving at different rates of speed, all uniform, all in straight lines, etc., all of which have a different local time. In every case, the faster it moves (with respect to object A, let's say), the MORE time dilation it experiences.
"Simply put, this result states that time moves more slowly for a moving object than it does for an object at rest."
What more is there to say? Other than that either (1) your unsupported conclusion about all objects on all geodesics having identical local times is wrong, or else (2) SR is wrong.
You will naturally pick (2). My own damn self, I would lean toward (1).
I said: "If you want to deny it, take it up with the relativists, eh?"
You always try to characterize the experts I quote as something that merely *I* am saying. You, on the other hand, cite nobody, but pretend you are speaking for not only yourself, but "all other physicists." Heh.
Even Al, in his dubious "resolution" of the twin paradox which you are so fond of, made an explicit distinction between the kinematic time effects and the gravitational effects:
"When relating to the coordinate system K' the behaviour explains itself as follows: During the partial processes 2 and 4 the clock U1, going at a velocity v, runs indeed at a slower pace than the resting clock U2."
He did not give his precise calculations, but it is clear that, in each case, he calculated the SR speed dilation effects separately and concluded that the gravitational effects were "exactly twice" that:
"However, this is more than compensated by a faster pace of U1 during partial process 3. According to the general theory of relativity, a clock will go faster the higher the gravitational potential of the location where it is located, and during partial process 3 U2 happens to be located at a higher gravitational potential than U1. The calculation shows that this speeding ahead constitutes exactly twice as much as the lagging behind during the partial processes 2 and 4."
Did he dispense with the odious asymmetry? Hell no: "According to both descriptions the clock U2 is running a certain amount behind clock U1 at the end of the observed process."
As previously noted, had clock U1 been the one arbitarily chosen then it, rather than clock U2, would have been the one that "ran behind" under the same "analysis" (in reverse).
But, again, you see none of this, and will no doubt continue to insist that gravitational and speed effects on time are simply indistinguishable.
Al said: "U2 happens to be located at a higher gravitational potential than U1."
"Happens to be," eh? Where, exactly, was the (non-existent) source of this field located, I wonder? 1000 miles away? I million? He doesn't exactly say. How large was the (imaginary) mass creating this field, I wonder? Big as our sun? 10 times as massive? He doesn't say. I guess it just "happens to be" wherever he thinks it should be, and as massive as he thinks it should be. Well, now, aint that special?
But, ya see, here's the thing...acceleration is completely relative because, like, who knows, it "could be" a magically appearing but unseen massive body causin the acceleration. Like, dark matter, ya know?
I guess the little rocket that accelerated the clock in frame K kinda jumped over and attached itself to the other clock at the very instant the magical field suddenly appeared too, eh? Just common sense that it would, of course, what with that powerful field comin along and the other clock needin some protection from it, and all. I mean, like, what rocket wouldn't, ya know?
I can kinda hear Al shoutin from his grave right now, eh:?
"Bondi, Synge,and alla y'all infidel bastards can kiss my lilly white ass. It's my damn theory of relative motion, and I'm entitled to base my physics on any damn premise I make up. You git any nobel prizes for figurin out the photo-electric effect? Yeah, that's what I thought. Don't question a genius, dumbasses!"
By the same token, you don't need a "third person" to determine if two objects are moving with respect to each other. Either the two objects are maintaining the same distance from each other (in which case they aint movin, relative to each other) or they aint, in which case at least one of them if "really" moving.
I have agreed to that several times, for a given definition of "really".
One Brow said: "Under that definition, one can deviate from a geodeisic without accelerating (as the ship does in K')"
Jesus H. Christ. We went through this at length, and finally had to "ask Colton." Both clocks are accelerating in K'. Einstein himself says the one "moving" is "accelerating." The other, though not moving, is accelerating by virtue of external forces acting on it (including, but not limited to, gravity).
I seem to recall you complaining about how I attached to words without understanding what they mean. Here, you are doing the same thing. If acceleration means "deviate from an inertial path", where an inertial path is defined in the sense of constant speed in a straight line, then in K' there is no acceleration of U2, but U1 does accelerate. If acceleration means "deviate from a geodeisic", then in K' U2 does accelerate, but U1 does not. These two meanings are different, and need different words to describe them. If you want to understand this at a deeper level, you need to be able to make that distinction, and choosing to use a different word/phrase for a different phenomenon is a good way to do that. Since we got colton's first set of responses (no, I have not heard anything since), I have consitently used acceleration in the first sense only. To use the word to mean both things, and to treat those to things as if they are the same, is pure equivocation.
It does no good. You always pop back up to reassert the same positions you were forced to abandon. Deviation from a geodesic is acceleration, Non-deviation is inertial, under GR. Again, the problem is even about GR to begin with. It is impossible to reason with you. You never hear or remember a word.
I agreed to use a specific terminology the way that you and colton used it. That terminology was *not* that non-deviation from a geodeisic was intertial in GR. We accepted inertial as defining movement in a straight line at constant speed. My positions did not change, but I did adapt my vocabularly, which is exactly what I said I would do. If you want to change the accepted vocabulary again, you'll need to do so clearly and unambiguously. These equivocations impair the conversation.
For example, GPS satellites are following geodeisics. Are they accelerating, or not? Are they inertial, or not?
A rocket blast off from earth. After the take-off, it uses the correct amount of fuel to maintain a contant speed of 50 mph (compared to the center of the earth) as it passes through the earths gravitational field headed toward Mars. In the period after the take-off, when it is maintaining constant speed, is it accelerating, or not? Is it inertial, or not? If your answers here are the same as in the previous paragraph, you are equivocating different phenomena under the same word, and we will need to agree on terminology that distinguishes them.
One Brow said: "K' is an SR viewpoint with an observer that leaves the geodeisic."
Newsflash: Special relativity does NOT address issues of gravity. That is why the "general" theory was developed. Well, one reason, anyway, another being Einstein's determination to try to "relativize" acceleration.
The gravity is just the explanation of movement within a geodeisic by U1 in K'.
A couple of things for you to consider (fat chance).
1. You want to rely on the EP, which tries to say gravitation IS acceleration.
An ontological interpretation of the EP, but the EP is an epistemological statement, not ontological. The EP does not say gravity is acceleration (otherwise it would not need the exception made for gravitational experiments), but that gravity is indistinguishable from acceleration empirically for many sorts of phenomena.
2. Gravitation, on its own, does NOT produce a uniform speed or a uniform velocity. It produce CONSTANT (ever-increasing) acceleration.
This is true in the first sense of acceleration defined above, but not in the second sense. Gravity produces the geodeisics that objects follow, it does not cause them to leave geodeisics.
If left to the accelerative aspects of gravitation alone, one would soon exceed the speed of light (unless he "changed direction" due to external influences). This might be a massive planet.
I think you'll find that if you do the math, you can't create conditions where gravity can accelerate something beyond the speed of light with a finite mass.
Colton said no such thing. Ask him if all objects in the universe which are "on a geodesic" all experience the exact same local time. If he says "yes," ask him if he believes SR is completely false.
If you like, I will ask him. If he answers yes and no, respectively, as I would, then what will you say?
One Brow said: "You mean get him to agree with me some more?"
No, I mean let him say things that contradict you so that you can then tell yourself that he agrees with you.
When he said something that contradicted how I understood a word to be used, I corrected myself. If he says anything that contradicts a basic understanding of mine, I will correct myself.
One Brow said: "You are incorrect. SR/GR says that, to the degree the statement makes sense at all without establishing a rest frame, time passes at the same rate for both Pat and Chris at long as both stay in geodeisics."
... You have presented no arguments to support your conclusion, nor do you intend to.
Actually, I did present a couple of arguments, you have not responded to them. I will happily present one of them again. You will, of course, ignore it again.
One way to see that Pat and Chris experience the same local time passage is to find a reference frame that at all times has the same delay in the travel of light between this third frame and Pat as between this third frame and Chris. So, in the sense that things happen to Pat and Chris at the same time, an observer in this reference frame will see them at the same time. As it happens, if Pat is moving at .6 comparted to Chris, this observer will be moving at .3c compared to both Pat and Chris. It will see Pat and Chris age at the same rate. The only observer that always sees Pat and Chris simultaneously (in this sense) sees them age at the same rate.
One Brow said: "I understand that you want to say there is some major, unbridgeable distinction between kinetic and gravitational effects on time."
I don't necessarily "want to say" any such thing. Relativity both special and general, could be complete bullshit, for all I know.
SR says that time dilates with speed IN ORDER TO claim that the speed of light will always appear to be the same to all observerss.
GR posits gravitational time distortion as a separate and distinct phenomenon. If you want to deny it, take it up with the relativists, eh? I'm simply assuming their premises, for the sake of this discussion.
Kinetic time dilation: the object that leaves the geodeisic experiences less time. The more stongly it diverts, the less proper time it experiences.
GR time distortion: the object that closely follows the geodeisic experiences more time. The more closely it follows the geodeisic, the more time it experiences.
Using a field interpretation of GR, I can see why you think they would be completely separate effects. Under the geometric interpretation, they are two sides of the same coin. To be clear, any time you use the term "geodeisic", you are using the geometric interpretation. I think both interpretations have value. I hink understanding both interpretations offers an insight into the phenomenon.
One Brow said: "Describe how one could then experience more time thant the other. What does that mean, in light of this observation?"
"This observation" is irrelevant. SR, not me, "describes" how one could then experience more time than another:
SR does not extend past noting that the two observers see things differently. You have to add you personal interpretations to the machinery of SR to say one person is really experiencing time dilation. The standard way is to add a rest frame to compare them to within which you can use the machinery of SR, but the rest frame is not a part of SR. You want to avoid that step, but you have offered nothihng in it's place. This is your interpretation to make, not SR's.
Al said: "U2 happens to be located at a higher gravitational potential than U1."
"Happens to be," eh? Where, exactly, was the (non-existent) source of this field located, I wonder? 1000 miles away? I million? He doesn't exactly say.
It is however far near or far away it needs to be, and moves however itneeds to move, to explain in K' that movement of U1 without leaving a geodeisic. Einstein says the force must exist because it explains the movement, and the only force known that creates movement in a geodeisic is gravity. He does not postulate the force to create the movement.
But, ya see, here's the thing...acceleration is completely relative because, like, who knows, it "could be" a magically appearing but unseen massive body causin the acceleration. Like, dark matter, ya know?
Riffing on the ontological implications is missing the point of K'. K' is not offered to explain ontological phenomena.
I guess the little rocket that accelerated the clock in frame K kinda jumped over and attached itself to the other clock at the very instant the magical field suddenly appeared too, eh?
This type of sentence is the result of your identifying two different phenomena with the common name "acceleration". The movement of U1 in K' can not be caused by a rocket or any similar thing.
"One of the fundamental results of Albert Einstein's special theory of relativity is a phenomenon known as time dilation. Simply put, this result states that time moves more slowly for a moving object than it does for an object at rest."
When he says "Simply put", do you think what follows will emphasize accuracy at the expense of being readable and comprehensible?
Take object A, and call it "at rest." Then take object B which is separating from A at the rate of one mile per hour. Object B is now "moving" with respect to A, and consequently times move more slowly for B than A.
Now take object C, which is separating from A at the rate of 2 miles per hour (and from B at 1 mph). Time for C will be less than for both B and A.
Note that, at this point, you could just ignore A and simply say that C is moving relative to B.
Take objects D, E, F, G, etc., ad infinitum. Progressively add 1 mph, or any fraction thereof, to the rate of its separation from A.
You can end up with an infinite number of objects all moving at different rates of speed, all uniform, all in straight lines, etc., all of which have a different local time. In every case, the faster it moves (with respect to object A, let's say), the MORE time dilation it experiences.
In every case, the faster it moves (with respect to object A, let's say), the MORE time dilation it experiences with respect to object A. Agreed.
"Simply put, this result states that time moves more slowly for a moving object than it does for an object at rest."
What more is there to say? Other than that either (1) your unsupported conclusion about all objects on all geodesics having identical local times is wrong, or else (2) SR is wrong.
You will naturally pick (2). My own damn self, I would lean toward (1).
I pick (3) nothing in your example says that the local time experience of C or G differs from the local time experience of A.
Let's limit the objects to 10, A-J (or pick any finite number). Would you agree that in every case, the faster it moves (with respect to object A, let's say), the LESS time dilation it experiences with respect to object J? If there a reason to say the frame where A is at rest has ontological superiority to the frame where J is at rest?
You always try to characterize the experts I quote as something that merely *I* am saying. You, on the other hand, cite nobody, but pretend you are speaking for not only yourself, but "all other physicists." Heh.
I do not treat the quotes of physicists as something you are saying. I do treat your interpretations of the quotes of physicists as something you are interpreting, and I think that is fair. Compared to the physicist we have been quoting, our attempts are the equivalent of one of us trying to translate Russian poetry using a Russian-English dictionary with no training in Russian, and the other using that same dictionary after studying Russian for a year. Neither of us compares to a person fluent in both Russian and English, of course.
But, again, you see none of this, and will no doubt continue to insist that gravitational and speed effects on time are simply indistinguishable.
I am probably guilty of over-emphasizing the geometric interpretation in our discussion. I think this is partly because I am a mathematician, and also partly because I am trying to get you to see there are other ways of interpreting what is happening that are equally valid. It would be going to far to say I think the effects are indistinguishable on an ontological level. However, there is a very deep commonality to the effects that I have seen no evidence you have understood.
I said: "Take object A, and call it "at rest."
You responded: "If there a reason to say the frame where A is at rest has ontological superiority to the frame where J is at rest?"
Heh, and you dispute my parody? Again, just start with the first sentence of the wiki problem and start screaming that NO problems, hypothetical or otherwise, can EVER be addressed because no one can ever say that any body is "at rest." The whole question is totally meaningingless and SR does NOT purport to address ANY situtaion where there is any assumption of motion or rest imputed to a particular object!
All you ever want to do is see how it looks according to some observer you create, and deny that any working frame can even be posited. This is not a question of how it looks to a particular observer, get it?
And you deny that you make this mistake, eh?:
"1. SR predictions depend on what a particular observer sees or thinks
2. If two or more observers can assess motion from different standpoints, that, in and of itself, makes motion "relative."
You seem utterly incapable of distinguishing the difference between what some guy, some where, might see from HIS subjective perspective and what is in fact the case.
The whole question is simply about what SR predicts, given case X. Case X is theoretically possible, so there is no reason to object to it as "impossible." And there is no reason to object to a hypothetical question on the grounds that it is not known whether the hypothetical condition has been fulfilled.
You position when addressing my question, always effectively boils down the claim that:
SR predicts NOTHING except that there can be no predictions. The only statement SR makes is that there are no answers, and can never be any answers, to any questions about motion, because it only says that all states of motion are unknown and unknowable.
SR makes one, AND ONLY ONE, claim of any kind, to wit: THERE IS NO ABSOLUTE MOTION, ALL MOTION IS RELATIVE!!!!!!
I said: "Take object A, and call it "at rest."
You responded: "If there a reason to say the frame where A is at rest has ontological superiority to the frame where J is at rest?"
Heh, and you dispute my parody? Again, just start with the first sentence of the wiki problem and start screaming that NO problems, hypothetical or otherwise, can EVER be addressed because no one can ever say that any body is "at rest." The whole question is totally meaningingless and SR does NOT purport to address ANY situtaion where there is any assumption of motion or rest imputed to a particular object!
You didn't answer the question, you ducked. Let's look at object H. Does it slow down by the amount SR predicts assuming A is at rest, the amount SR predicts assuming that J is at rest, or by some other amount, according to you?
Of course, my answer is that time flows at the same rate for H as it does for A, J and all the other letters.
All you ever want to do is see how it looks according to some observer you create, and deny that any working frame can even be posited. This is not a question of how it looks to a particular observer, get it?
If you are talking the effects of time dilation on objects that stay in a geodeisic, it is entirely about how they look to outside observers. Time dilation effects don't become objective until two objects are so close together that the differences based on the relativity of simultaneity are overshadowed by the other relativistic effects.
And you deny that you make this mistake, eh?:
"1. SR predictions depend on what a particular observer sees or thinks
SR predicts that different observers will see different things. However, the predictions of SR are not dependent on the existence or thoughts of observers.
2. If two or more observers can assess motion from different standpoints, that, in and of itself, makes motion "relative."
You can assess length from different standpoints, but length is not relative. Many types of motion are relative by their nature, not by the assessments of observers.
You seem utterly incapable of distinguishing the difference between what some guy, some where, might see from HIS subjective perspective and what is in fact the case.
You are utterly incapable of defining what "the case" is supposed to be. If you can't define it, how can I differentiate it from anything?
The whole question is simply about what SR predicts, given case X. Case X is theoretically possible, so there is no reason to object to it as "impossible." And there is no reason to object to a hypothetical question on the grounds that it is not known whether the hypothetical condition has been fulfilled.
In the A-J scenario, the prediction is that each object experiences local time at the same rate.
You position when addressing my question, always effectively boils down the claim that:
SR predicts NOTHING except that there can be no predictions.
I have given you predictions before, you rejected them.
The only statement SR makes is that there are no answers, and can never be any answers, to any questions about motion, because it only says that all states of motion are unknown and unknowable.
In some scenarios, unique answers are only available within certain boundary conditions. This is hardly unique to relativity.
SR makes one, AND ONLY ONE, claim of any kind, to wit: THERE IS NO ABSOLUTE MOTION, ALL MOTION IS RELATIVE!!!!!!
Except for rotational motion, and that's hardly unique to relativity theory. Newton's mechanics were also relative.
One Brow said: "You didn't answer the question, you ducked. Let's look at object H"
I have read your post, and I'm not sure I'm going to because you fail to understand the substance of anything I say. I'll try this one more time:
Take objects A-J and assume that ALL of them assume that A is at rest. Now what does SR predict about differing time frames?
Edit: Haven't read your post
One Brow said: "Of course, my answer is that time flows at the same rate for H as it does for A, J and all the other letters."
You do the math on this?
Take the wiki example, but now assume that instead of only one ship being blasted off, 9 are. One is moving at .1c, one at .2c, etc. Will each one now calculate the earth's clock to be running slow by the same amount, or will that vary with differing speeds, eh?
Take objects A-J and assume that ALL of them assume that A is at rest. Now what does SR predict about differing time frames?
Are you suggesting that what the objects assume to be true will change the answer? Will a person in object H have time move differently if they assume A is at rest versus if they assume J is at rest? I don't think so.
You do the math on this?
Take the wiki example, but now assume that instead of only one ship being blasted off, 9 are. One is moving at .1c, one at .2c, etc. Will each one now calculate the earth's clock to be running slow by the same amount, or will that vary with differing speeds, eh?
Your initial take on A, B, etc. didn't say anything about blasting off, just that they were already moving.
However, to answer your question, each one will calculate the earth's clock to run at a different speed. Does that mean the earth's clock runs at nine different speeds? No.
I said: "SR makes one, AND ONLY ONE, claim of any kind, to wit: THERE IS NO ABSOLUTE MOTION, ALL MOTION IS RELATIVE!!!!!!"
"Except for rotational motion, and that's hardly unique to relativity theory. Newton's mechanics were also relative."
Wrong as to your "sole exception and SR." Einstein fully admitted that, within the confines of SR, LINEAR acceleration was absolute. He didn't like that, philosophically, so he later tried, with GR, to also relativize acceleration/inertial. As a consequence, under his interpretation, all acceleration is gravity and all gravity is acceleration. The experts I have cited claim he failed in this attempt.
One Brow said: "Riffing on the ontological implications is missing the point of K'. K' is not offered to explain ontological phenomena."
Wrong on this score, too. For Einstien, who created this K and K' analysis, gravitation and acceleration were absolutely and ontologically "the exact same thing." Modern physicists have (rightfully, in my opinion) rejected this view, and Al's notion of "general relativity" with it. See the emphasized caveat given by wiki on this score, to wit: "It should be emphasized that according to Einstein's explanation, this gravitational field is just as "real" as any other field, but in modern interpretation it is only perceptual because it is caused by the traveling twin's acceleration."
SR is a theory of motion, GR is a theory of gravity, or so most modern physicists see it. I don't even want to talk about GR as a theory of motion when discussing SR problems (as you have noted, GR does nothing to invalidate SR, in fact most think it is based on much more solid ground than GR).
"
One Brow said: "However, to answer your question, each one will calculate the earth's clock to run at a different speed. Does that mean the earth's clock runs at nine different speeds? No."
Of course not, but it DOES mean that all 9 do NOT share the exact same local time.
One Brow said: "Your initial take on A, B, etc. didn't say anything about blasting off, just that they were already moving."
No, my initial take said A was "at rest," and I didn't mean at rest with respect to itself like Zeno's arrow. I meant at rest for all concerned in the hypothethical question.
One Brow said: "Are you suggesting that what the objects assume to be true will change the answer?"
Of course not. I have consistently said that what they "assume" about what is true has nothing, per se, to with what is true (they may be right, or they may be wrong).
If 9 ships blasted off, each going .5c, then all would see their time change, relative to earth's identically. If they are going different speeds, they won't see it that way, get it?
Kinematic time dilation simply is NOT determined solely by whether or not an object is inertial (on a geodesic). It is dependent upon relative speed alone.
If 9 ships blasted off, each going .5c, then all would see their time change, relative to earth's identically. Conversely, they will all see each other's clock as identical to their own. Why? Because they are going the same speed, and hence are in THE SAME inertial frame (not just an inertial frame, i.e., any old inertial frame you could dream up), get it?
If 9 ships blasted off, each going .5c, then, according to SR they will, in fact, all age the same. SR predicts the opposite for Pat and Chris, who are NOT in the same inertial frame.
One Brow said: "Will a person in object H have time move differently if they assume A is at rest versus if they assume J is at rest? I don't think so."
Thank you. Ponder on what you just said for a spell. You are exactly right.
One Brow said: "You can assess length from different standpoints, but length is not relative."
We've been through this before. Length IS relative, according to SR, at least. It too changes with speed. Time is relative, length (distance) is relative, it's all relative except for speed itself, which is absolute. Distance (length) divided by time always gives a single answer for the speed of light.
This is just another way of saying that both time and distance change with speed. Since an object can be travelling at virtually an infinite number of speeds and be "on a geodesic" in every single case, this PROVES that every object "on a geodesic" can NOT age the same.
Well, it "proves" it if you believe SR, anyway. SR dictates no other conclusion.
A car is moving east from East Saint Louie on interstate 64 at the rate of 60 mph. Now what does the relativists "logic" (philosophy) tell you about that?
It tells you that you have just said a "meaningless" thing, that's what. For all that can be ABSOLUTELY PROVEN, it could simply be that the car is standing still and that interstate 64, all towns, all trees, and all other things moving with the earth are simply moving west. Since it can't be ABSOLUTELY PROVEN, no one can possibly know which is which. Anyone who pretends to have reasonable grounds to prefer one view over another is simply a parochial bigot.
Now that's what I call "science," sho nuff!
Such physics relativists simply carry their unameliorated moral relativism over to objective physical reality, I guess.
If someone pulls off of interstate 64; enters a town of 500; murders, dismembers, and cannibalizes every human over the age of 12; and then rapes, tortures and enslaves every child 12 and under, that cannot possibly be "wrong."
Why not? Well, a couple of reasons, I guess.
1. There could be a society, or at least a person (like the one committing the mayhem here) who does not believe it is wrong. Their sense of right and wrong is just as valid as anybody's, so it can't be wrong.
2. Furthermore, it cannot be ABSOLUTELY PROVEN that it is wrong. Like Plato done said, if it aint univocally eternal, immutable, and absolute, it aint truth.
Q.E.D, and all, ya know?
I said: "SR makes one, AND ONLY ONE, claim of any kind, to wit: THERE IS NO ABSOLUTE MOTION, ALL MOTION IS RELATIVE!!!!!!"
"Except for rotational motion, and that's hardly unique to relativity theory. Newton's mechanics were also relative."
Wrong as to your "sole exception and SR." Einstein fully admitted that, within the confines of SR, LINEAR acceleration was absolute.
That's like saying within the confines of first grade math, you can't do calculus. Why do you think that would mean anything?
He didn't like that, philosophically, so he later tried, with GR, to also relativize acceleration/inertial. As a consequence, under his interpretation, all acceleration is gravity and all gravity is acceleration. The experts I have cited claim he failed in this attempt.
Yes, not every type of acceleration is indistinguishable from gravity. We've covered that. Also, GR was not an attempt to say acceleration was gravity. ONe of the clear effects of GR is that gravity is unlike other types of acceleration in a very important way: gravitational forces do not cause deviation from geodeisics.
One Brow said: "Riffing on the ontological implications is missing the point of K'. K' is not offered to explain ontological phenomena."
Wrong on this score, too. For Einstien, who created this K and K' analysis, gravitation and acceleration were absolutely and ontologically "the exact same thing."
Einstien describes different effects emerging from the acceleration in K versus that in K'. If they were the same thing in his mind, he would have described them as having the same effects.
SR is a theory of motion, GR is a theory of gravity, or so most modern physicists see it.
Modern physicists, like the physicists of Einstein's time, see SR as a part of GR, it is GR applied to a limited set of cercumstances. colton also confirmed that directly for you.
One Brow said: "However, to answer your question, each one will calculate the earth's clock to run at a different speed. Does that mean the earth's clock runs at nine different speeds? No."
Of course not, but it DOES mean that all 9 do NOT share the exact same local time.
Why?
One Brow said: "Your initial take on A, B, etc. didn't say anything about blasting off, just that they were already moving."
No, my initial take said A was "at rest," and I didn't mean at rest with respect to itself like Zeno's arrow. I meant at rest for all concerned in the hypothethical question.
So, you meant to establish A as the preferred rest frame, and any obersevers on the other objects would calculate their numbers on that basis? Works for me.
One Brow said: "Are you suggesting that what the objects assume to be true will change the answer?"
Of course not. I have consistently said that what they "assume" about what is true has nothing, per se, to with what is true (they may be right, or they may be wrong).
Yet, you want them all to assume A is in the rest frame.
If 9 ships blasted off, each going .5c, then all would see their time change, relative to earth's identically. If they are going different speeds, they won't see it that way, get it?
You mean "calculate". None of them would see their own time change.
Kinematic time dilation simply is NOT determined solely by whether or not an object is inertial (on a geodesic). It is dependent upon relative speed alone.
The perception of time dilation is based on relative speed. To compare time meaningfully, clocks must be synchronized, which requires an initial close proximity. For the time dilation to be meaningful, the two objects must be in close proximity a second time, after the movement. At that point, whoever left the geodeisic will have experienced less time. If neither has left their respective geodeisic, they will have experienced equal time.
If 9 ships blasted off, each going .5c, then all would see their time change, relative to earth's identically. Conversely, they will all see each other's clock as identical to their own. Why? Because they are going the same speed, and hence are in THE SAME inertial frame (not just an inertial frame, i.e., any old inertial frame you could dream up), get it?
I agree.
If 9 ships blasted off, each going .5c, then, according to SR they will, in fact, all age the same. SR predicts the opposite for Pat and Chris, who are NOT in the same inertial frame.
To the extent such a prediction can be meaningfully made, SR predicts Pat and Chris will age the same. I have already given you a couple of reasons to understand this (mirrored differences in mirrored future events, the point of view of a person who see them with the same light-delay). You have not addressed these scenarios, instead you are just repeating your position. I thought you disapproved of that behavior? Do you have anything beyong this repetition? What does it mean, to you, to say pat and Chris go through different amounts of time? How can that be seen? What effects does it have? Is there anything more to this claim than "because I say so"?
One Brow said: "Will a person in object H have time move differently if they assume A is at rest versus if they assume J is at rest? I don't think so."
Thank you. Ponder on what you just said for a spell. You are exactly right.
Of course, I have been saying that all along.
One Brow said: "You can assess length from different standpoints, but length is not relative."
We've been through this before. Length IS relative, according to SR, at least. It too changes with speed. Time is relative, length (distance) is relative, it's all relative except for speed itself, which is absolute. Distance (length) divided by time always gives a single answer for the speed of light.
The length of an object in your reference frame does not change. You measure a different length for objects outside your reference frame as your speed changes, but that is a function of what you measure, not of the length itself. If I am traveling at .6c relative to a meter stick, I'll see that stick as measuring .8m. But the stick didn't change, it is still one meter long.
This is just another way of saying that both time and distance change with speed. Since an object can be travelling at virtually an infinite number of speeds and be "on a geodesic" in every single case, this PROVES that every object "on a geodesic" can NOT age the same.
Well, it "proves" it if you believe SR, anyway. SR dictates no other conclusion.
You are invoking the speed of one object to change the time passage in another object. That is magic, not physics.
A car is moving east from East Saint Louie on interstate 64 at the rate of 60 mph. Now what does the relativists "logic" (philosophy) tell you about that?
That it's movement is being measured compared to the road it is one, by convention.
It tells you that you have just said a "meaningless" thing, that's what. ...Anyone who pretends to have reasonable grounds to prefer one view over another is simply a parochial bigot.
Or, is using a concept external to relativity theory, such as the conservation of mass-energy.
Looked at another way:
10 objects, all at virtually the same point in spacetime, diverge from each other and take different paths. Years later, they all reconverge. The one "on the geodesic" will have experienced the "most time" even though it travelled the "shortest distance" (geodesic). Why is that? Kinda seems he mighta got there in the least time, not the most, ya know?
It is because the other 9 would all have had to travel at higher rates of speed to get there at the same time, because they had to go further. They had to speed up, and increased speed equals dilated time. Simple SR, nuthin unique to GR.
One Brow said: "To the extent such a prediction can be meaningfully made, SR predicts Pat and Chris will age the same. I have already given you a couple of reasons to understand this (mirrored differences in mirrored future events, the point of view of a person who see them with the same light-delay). You have not addressed these scenarios, instead you are just repeating your position.
You keep repeating this no matter how much evidence accumlulates against you. I can't address your irrevelancies at length because they make no sense.
Tell you what. I'll just bet you $10,000.00 how's that? And, no, Colton will not be the sole judge. This is even worse that the even/odds dispute we had.
"For the time dilation to be meaningful, the two objects must be in close proximity a second time, after the movement."
Wrong. Absolutely wrong. Time dilation is quite "meaningful" in the abstract. Just another example of this fallacious line of "reasoning:"
I said: "A third implicit mistake you have been making (and Colton, to the extent I have already noted--did he ever respond to my questions, btw) is that no SR prediction is "valid" unless and until the particular circumstances have been empirically confirmed. Knowledge and/or confirmation of the facts has NOTHING to do with the prediction itself."
Let's just bet $10,000, whaddaya say!?
One Brow said: "You are invoking the speed of one object to change the time passage in another object. That is magic, not physics."
You are HOPELESSLLY confused.
One Brow said: "Einstien describes different effects emerging from the acceleration in K versus that in K'. If they were the same thing in his mind, he would have described them as having the same effects."
Rather than always deducing what someone "must have" said, you should just read what they say sometime, ya know?
I remember an extended discussion I had with Write4u at Jazzfanz when Girichuck got benched by Sloan. He had it in his mind that Sloan "must have" (and therefore DID, in his mind, of course) done or said a certain thing (I've forgotten his specific claim now) which reporters and eye-witnesses said did not happen. Nothing could change his mind. Even though he wasn't there, the reporters and witnesses were all simply lying to protect Sloan or simply blind.
10 objects, all at virtually the same point in spacetime, diverge from each other and take different paths. Years later, they all reconverge. The one "on the geodesic" will have experienced the "most time" even though it travelled the "shortest distance" (geodesic). Why is that? Kinda seems he mighta got there in the least time, not the most, ya know?
It is because the other 9 would all have had to travel at higher rates of speed to get there at the same time, because they had to go further. They had to speed up, and increased speed equals dilated time. Simple SR, nuthin unique to GR.
Earlier, I gave you an example of two objects that left the same point in different directions, where the one in the geodeisic traveled further and faster to get to the same point. I'm not sure you ever understood it, but eventually you blew it off.
One Brow said: "To the extent such a prediction can be meaningfully made, SR predicts Pat and Chris will age the same. I have already given you a couple of reasons to understand this (mirrored differences in mirrored future events, the point of view of a person who see them with the same light-delay). You have not addressed these scenarios, instead you are just repeating your position.
You keep repeating this no matter how much evidence accumlulates against you. I can't address your irrevelancies at length because they make no sense.
If you don't understand very simple scenarios and obvious examples, you should refrain from speaking about how the evidence is accumlating. If you had the knowledge you needed to understand the evidence, you would have figured out the examp[les I have presented by now.
Tell you what. I'll just bet you $10,000.00 how's that? And, no, Colton will not be the sole judge. This is even worse that the even/odds dispute we had.
No matter how certain I was of the outcome, it would be immoral for me to bet that amount of money, because I could never pay it. I can spare $10-$20 at the end of February, if you really want to bet.
However, I doubt we will find a physicist who will say more than colton already has. For the most part, they don't think questions like observer-indepent aging in a Pat/Chris scenario are the right sort of questions to begin with, from what I can tell. Still, if you want to make that bet, I'm game. Hhow do you proposed it would be judged? What would be the question posed, and what answers would consist of winning, losing, or neither? Even if I lost, it would be worth it just to meet you face-to-face for a change.
"For the time dilation to be meaningful, the two objects must be in close proximity a second time, after the movement."
Wrong. Absolutely wrong. Time dilation is quite "meaningful" in the abstract. Just another example of this fallacious line of "reasoning:"
It's a key notion of relativity, actually. Have you read up on the relativity of simultaneity?
http://en.wikipedia.org/wiki/Relativity_of_simultaneity
If you're not in close proximity to another clock, comparing times on that clock to yours is difficult to interpret.
I said: "A third implicit mistake you have been making (and Colton, to the extent I have already noted--did he ever respond to my questions, btw) is that no SR prediction is "valid" unless and until the particular circumstances have been empirically confirmed. Knowledge and/or confirmation of the facts has NOTHING to do with the prediction itself."
Nothing that colton nor I has said implies this, and I have actively argued against.
No, no further reposne. I'll prod him.
One Brow said: "You are invoking the speed of one object to change the time passage in another object. That is magic, not physics."
You are HOPELESSLLY confused.
One of us is.
One Brow said: "Einstien describes different effects emerging from the acceleration in K versus that in K'. If they were the same thing in his mind, he would have described them as having the same effects."
Rather than always deducing what someone "must have" said, you should just read what they say sometime, ya know?
Which part did you disagree with?
1) Does Einstein attribute a mirrored end result in K (U2 exeriences less proper time) versus K' (U1 experiences less time)? No, in both K and K' U2 experiences less time.
2) Does Einstein claim that the time distortion effects of movement are random, so there is no reason to expect consistentcy? No, he gives calculations.
If he treated K and K' as being exact mirrors of each other, he would have given mirrored calculations to produce mirrored results. INstead, he offers different calculations to produced non-mirrored results.
See, I didn't just read the article, I understood it.
I remember an extended discussion I had with Write4u at Jazzfanz when Girichuck got benched by Sloan. He had it in his mind that Sloan "must have" (and therefore DID, in his mind, of course) done or said a certain thing (I've forgotten his specific claim now) which reporters and eye-witnesses said did not happen. Nothing could change his mind. Even though he wasn't there, the reporters and witnesses were all simply lying to protect Sloan or simply blind.
Are you sure I didn't have that conversation with him? He does think we are the same person. Is conversation participation raletive to the observer?
Let's bet. Your position, as I understand it, is this:
Any and all objects in the entire universe which are on "a geodesic," irrespective of just what that particlar geodesic for any one object, all "age the same," i.e., have the same local time.
I want this question framed in a SR context. As you have put it, in that context (flat spacetime, etc.), all objects which are in any inertial frame, not necessary any "shared" inertial frame where they are both going the same speed, but ANY interial frame whatsoever, will have clocks that read the same.
That your position?
One Brow said: "If you had the knowledge you needed to understand the evidence, you would have figured out the examp[les I have presented by now."
I have figured out by now that the concepts you think you are relying on to prove your point are irrelevant, time delay, relativity of simultaneity, etc., are misguided, and have told you why.
I think I know exactly where you are making your mistake, and I have pointed it out to you. Let's just bet.
Another way to put the question: "Two observers, each travelling in a straight line at a uniform speed without any external forces acting upon them in flat spacetime, are separating from each other at the rate of .5c.
Does SR predict that they will age the same, under those circumstances?"
Another way: "Two cars are travelling down interstate 64. One is moving at a uniform speed of 40 mph and one at 80 mph. In other words, an hour from now, they will be an additional 40 miles apart. The two have NEVER met and synchronized watches.
Does SR predict that they will age the same, under those circumstances?"
One Brow said: "Earlier, I gave you an example of two objects that left the same point in different directions, where the one in the geodeisic traveled further and faster to get to the same point."
This is wrong. It is the one not on the geodesic who travels "further and faster." The one on the geodesic does, however, experince "more time," even though it is taking the "shortest path," as I said. Which proves the point in question. Time slows down for the traveller "going faster."
I am ignoring any gravitational time contraction, of course, which is not required. I am only speaking of the kinematic dilation effects.
Since you keep denying this also, here's yet another authoritative source:
"In 1918, Einstein described Mach's principle as a philosophical pillar of general relativity, along with the physical principle of equivalence and the mathematical pillar of general covariance. This characterization is now widely regarded as wishful thinking. Einstein was undoubtedly inspired by Mach's relational views, and he hoped that his new theory of gravitation would "secure the relativization of inertia"...The term "general relativity" is thus something of a misnomer, as pointed out by Hermann Minkowski and others. The theory does not make spacetime more relative than it was in special relativity. Just the opposite is true: the absolute space and time of Newton are retained."
http://einstein.stanford.edu/SPACETIME/spacetime2.html
"One Brow said: "Riffing on the ontological implications is missing the point of K'. K' is not offered to explain ontological phenomena...
Einstien describes different effects emerging from the acceleration in K versus that in K'. If they were the same thing in his mind, he would have described them as having the same effects."
====
"But the distinction between “pseudo-gravity” and “true gravity” is precisely what Einstein denied. The equivalence principle asserts that these are intrinsically identical. Einstein’s point hasn't been fully appreciated by some subsequent writers of relativity text books...The point of the equivalence principle is that curving coordinates are gravitation, and there is no intrinsic ontological difference between “true gravity” and “pseudo-gravity”."
http://www.mathpages.com/rr/s5-06/5-06.htm
No ontological difference, eh?
SR purportedly deals with uniform motion, not accelerated motion (although many seem to claim that accelerated motion is perfectly analyzable in SR terms). Everyone seems to concede that acceleration does NOT cause the kinematic time dilation caused by uniform motion at differing speeds.
GR deals with a separate issue, i.e., accelerated motion, and calls it "gravity." Accelerated motion, or gravity, if you prefer, has its own effects on time, but these are separate and apart from, and in addition to, the kinematic effects produced by uniform motion.
SR predicts, as you have acknowledged, that as a object speeds up, time slows down for it. If it does NOT speed up, time will not slow down. It is not a matter of who knows what about *whether* it has actually slowed down, it is simply a matter of what will happen at higher rates of speed. As between two objects, the one travelling at the higher rate of speed will age less rapidly, and the one travelling at the lower rate of speed will age more rapidly.
Therefore, two objects, moving at different rates of speed in uniform (inertial) motion simply cannot age the same in SR. Taking an LR view, which merely posits an absolute frame of reference, such as the CMBR, they could be aging the same, because each could be going the exact same "absolute speed," and not necessarily a "different" speed. But for SR, any difference in speed in considered a true difference, because there is no absolute reference frame. In SR, two objects cannot be going the same speed if they are separating from each other. Therefore, they cannot age the same.
This all follows from the most elementary of SR principles, yet you complain that no one addresses the claims of your novel position. SR addresses them, as I have been pointing out for about 1400 posts now.
Let's bet, whaddaya say!?
In the wiki example, the travelling twin ages less. With this in mind, you have nonetheless been all over the board with respect to how that result could ever be an accurate prediction.
1. Most recently, you have repeatedly and emphatically (in the most cocksure manner) insisted that SR predicts they will age the same. Even Al's bogus "GR" proof does not make this claim.
2. You have previously asserted that SR says that if both insist that only the other is aging less rapidly, then both "are correct."
Both of these statements contradict SR predictions, but you try to draw some meaningless distinction to prove the wiki result will vary from case to case. Irrelevant claims such as "In the wiki example, one twin had red hair, in this example, neither twin has red hair, therefore the two cases are obviously different." Heh.
Stanford.edu said: "Einstein was undoubtedly inspired by Mach's relational views, and he hoped that his new theory of gravitation would "secure the relativization of inertia."
Note that the "relativization of inertia" would also be the "relativization of acceleration," just as the relativization of "tall" would also be the relativization of "short."
Nice try, Al, but....
Stanford.edu said: "In 1918, Einstein described Mach's principle as a philosophical pillar of general relativity, along with the physical principle of equivalence and the mathematical pillar of general covariance."
Even Al himself conceded that his "philosophical pillar," (Mach's principle) had to be abandoned.
Modern phsyicists tend to reject his "physical pillar" (ontological identity of acceleration and gravity) also.
His mathematical pillar (general covariance) has survived pretty well, as far as I know.
1 outta 3 aint a complete shutout.
For any two point, A & B, there is a third point, C, which is halfway between them. Light signals from A and B will therefore reach C at the same time.
Wow! That's absolutely amazing! So, what does that mean?
"That means that occupants of A and B will age the same, that's what!!
So, since every two objects have a midpoint, all objects, everywhere, will also age the same?
"You got it."
One Brow said: "You are invoking the speed of one object to change the time passage in another object. That is magic, not physics."
Heh.
One Brow said: "Nothing that colton nor I has said implies this, and I have actively argued against."
Colton was given a problem where, like the wiki problem, it was stipulated one object was moving away from another. In (partial) response, he claimed that no one could say which one was aging less rapidly unless and until the two were brought back together. You did NOT argue against his position. On the contrary, you enthusiastically endorsed it.
His statement implies that the clear predictions of SR are worthless and tell us nothing unless and until we can confirm the facts of each particular example where predictions come into play.
Just because you CAN compare clocks IF they come back together does NOT mean that you MUST compare clocks to know what SR predicts.
Nor does it mean, as your "reasoning" suggests, that because you can compare clocks if they come back together, as long as you don't compare them, SR predicts they will age the same.
Stanford.edu said: "The theory does not make spacetime more relative than it was in special relativity. Just the opposite is true: the absolute space and time of Newton are retained."
Synge said: “The Principle of Equivalence performed theessential office of midwife at the birth of general relativity . . . I suggest that the midwife be now buried with appropriate honours and the facts of absolute space-time faced”
Denialists say: "Face the "facts" of absolute space time!? Are you NUTS, Synge!? It's a straightup LIE and you have the audacity to call it a fact!? As long as I deny it, it CAN'T be true. I got my story and I'm stickin to it, see? I and all other physicists claim otherwise. Well, maybe except for that fool Bondi. Not Minkowsi, cause he aint even a physicist, he.s a mere mathematician, and probably a poor one at that. Ya can kiss my lilly white ass if you don't like it. Moron."
"[General Relativity] was the crowning achievement of Einstein's scientific career. Its name, however, is something of a misnomer. The theory does not extend the principle of relativity for uniform motion to nonuniform motion. It retains the notion of absolute acceleration—that is, acceleration with respect to space-time rather than with respect to other bodies. In this sense, general relativity is no different from Newtonian theory or special relativity....From the point of view of modern physics, the question to what extent general relativity fulfilled Einstein's original hopes of relativizing all motion is of secondary importance."
http://science.jrank.org/pages/8034/Relativity.html
Secondary importance!? Another moronic infidel, eh? Who's startin all these slanderous lies, I wonder?
One Brow said: "SR predicts that different observers will see different things. However, the predictions of SR are not dependent on the existence or thoughts of observers."
OK, fair enough, but in very paragraph preceding that, you claim: "If you are talking the effects of time dilation on objects that stay in a geodeisic, it is entirely about how they look to outside observers. Time dilation effects don't become objective until two objects are so close together that the differences based on the relativity of simultaneity are overshadowed by the other relativistic effects."
Heh, and you claim *I'm* confused. Besides contradicting yourself, you are simply wrong. The "gravitational" (as opposed to kinematic) time distortion is absolute in GR. It is seen the same by all observers, or so they say.
I said: "It tells you that you have just said a "meaningless" thing, that's what. ...Anyone who pretends to have reasonable grounds to prefer one view over another is simply a parochial bigot."
Your response: "Or, is using a concept external to relativity theory, such as the conservation of mass-energy."
External to relativity theory?
"If we suppose that a particular star is sufficiently distant, then the x component of its radial velocity (which is uniform and linear) will exceed the velocity of light. Such a circumstance being forbidden, we are forced to conclude that the earth is spinning, rather than the star revolving around the earth. We see that, in this sense, the limit c can be used to imply a specific frame of reference."
http://www.angelfire.com/az3/nfold/relativity.html
Al said: "The Einstein of 1915 implies that if two objects have two different velocities, we must regard one as having an absolutely higher velocity than the other because one object has been "really" accelerated."
You want to say: "Yet one might conjecture that if two objects move with different velocities wherein neither has a prior acceleration, then the spacetime curvature would be identical for each object and the objects' clocks would not get out of step."
Problem is: "But such a conjecture would violate the limiting case of special relativity (and hence general relativity); specifically, such a conjecture would be inconsistent with the constancy of the vacuum velocity of light in any reference frame. So then, general relativity requires that velocity differences are, in a sense, absolute."
http://www.angelfire.com/az3/nfold/relativity.html
Either concede that you are wrong, or let's bet!
So, then, what's the deal with this here twin paradox?:
"It was Einstein who set himself up for the paradox , writing that various examples "suggest that the phenomena of electrodynamics as well as of mechanics possess by favoring the idea that only purely relative motions are meaningfulno properties corresponding to the idea of absolute rest.
Einstein offered the scenario of two initially synchronized clocks at rest with respect to each other. One clock then travels around a closed loop, and its time is dilated with respect to the at-rest clock when they meet again...Clearly, if there is no preferred frame of reference, a contradiction arises: when the clocks meet again, which clock has recorded fewer ticks?"
===
OK, Al made a claim about absolute rest, and set himself up for the paradox, eh? Now what?
===
"The paradox stems from the fact that one cannot say which velocity is higher without a "background" reference frame. In Newtonian terms, the same issue arises: if one body is accelerating away from the other, how do we know which body experiences the "real" force? No answer is possible without more information, implying a background frame....
Einstein's appeal to spacetime curvature to address the frame of reference issue is similar to Newton's assertion that an accelerated body requires either an impulse imputed to it or the gravitational force. There is an inherent local physical asymmetry. Purely relative motion will not do.
"GR partly resolves the clock paradox...Einstein now holds that some accelerations are not strictly relative...only one body can have a higher absolute angular velocity with respect to the other because only one must have experienced an acceleration that distorts spacetime differently from the other."
http://www.angelfire.com/az3/nfold/relativity.html
===
So, as I said about 1400 posts ago, the paradox is "resolved" simply by retracting the erroneous claim that generated it, to wit: He had to quit "favoring the idea that only purely relative motions are meaningful" and cave in to absolute rest, absolute motion, and absolute acceleration.
Nice try, though, Al.
Edit: First quote, last post, should have read:
"It was Einstein who set himself up for the paradox by favoring the idea that only purely relative motions are meaningful, writing that various examples "suggest that the phenomena of electrodynamics as well as of mechanics possess no properties corresponding to the idea of absolute rest."
In SR, all observers in inertial frames will measure the speed of light to be the same, irrespective of the motion of either the source or the receiver.
For this to hold, either time, distance, or both MUST vary with speed. In SR, it is both.
Is we is, or is we aint, gunna bet? Let's bet!
Two populated planets, 30 light years apart. Neither is moving with respect to the other, so, in other words, they are going the same speed, whatever it is. They have the same time frame (although certainly NOT simultaneity of events, but that is totally irrelevent; it has nothing whatsover to do with clock rates).
Joe travels from planet A to planet B, never to return. What does SR predict with respect to the aging of Joe versus the inhabitants of each planet?
It predicts that during the time he travels, Joe will age less than the inhabitants of both planets. Why? Because while he is travelling, he is moving faster than all inhabitants of both planets.
Let's bet!
In the above example, Joe is approaching planet B and distancing himself from planet A. Due to doppler effects, the clocks on planet appear to be even slower and the ones on planet B faster.
So who will age more, while Joe is travelling, A or B? Neither, they will age the same. Why? Because they are going the same speed, and the doppler effect is totally irrelevant.
What if some guy somewhere sees it differently? Don't matter, totally irrelevant and won't change nuthin.
Let's bet!
But how about Joe? Will he age more than inhabitants of one planet than the other? Stupid question, how can he age more than himself?
Let's bet!
9-11-01: Some guy is hangin around on the 123rd floor of one of the twin towers, and it's gittin awful damn hot, so he decides to leave the building via the window.
He thinks to himself: "Cool! This is EXACTLY the same thing as bein in an inertial state in space." He don't think that for long, though, because once he busts himself up on the street he aint think nuthin. I guess it wasn't EXACTLY the same after all, eh? Purty close though, I betcha!
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