Preferred Frame Theory indistinguishable from SR
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From: PD on 6 Jul 2010 11:07 On Jul 5, 12:12 am, colp <c...(a)solder.ath.cx> wrote: > On Jul 5, 7:27 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jul 3, 6:07 pm, colp <c...(a)solder.ath.cx> wrote: > > > > On Jul 4, 2:10 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Jul 3, 1:04 am, colp <c...(a)solder.ath.cx> wrote: > > > > > > On Jul 3, 2:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jul 1, 6:25 pm, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > On Jul 2, 2:26 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Jul 1, 12:53 am, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > > > On Jul 1, 11:37 am, Koobee Wublee <koobee.wub...(a)gmail.com> wrote: > > > > > > > > > > > On Jun 30, 4:20 pm, artful wrote: > > > > > > > > > > > > On Jul 1, 8:47 am, colp wrote: > > > > > > > > > > > > The statement that "moving clocks run slow" isn't an > > > > > > > > > > > > oversimplification, it is directly inferred from Einstein's > > > > > > > > > > > > "Electrodynamics of Moving Bodies". > > > > > > > > > > > > It IS an over simplification. There is more to SR than just clocks > > > > > > > > > > > running slow. > > > > > > > > > > > Nonsense and mysticism. <shrug> > > > > > > > > > > A postulate is just an assumption with better table manners. > > > > > > > > > Yes, indeed. By DEFINITION, a postulate is something that is ASSUMED. > > > > > > > > > In science, the test of a postulate is based on experimental check of > > > > > > > > the *consequences* of postulates. A direct test of the postulate is > > > > > > > > not required. > > > > > > > > One such test is the test for paradoxes arising from one or more > > > > > > > postulates. For example, the following two postulates lead to a > > > > > > > paradox, meaning that not all the postulates are correct: > > > > > > > > 1. Statement 2 is true. > > > > > > > 2. Statement 1 is false. > > > > > > > > The paradox that arises from the postulates of Einstein's > > > > > > > "Electrodynamics of Moving Bodies" can be described as follows: > > > > > > > > "Examples of this sort, together with the unsuccessful attempts to > > > > > > > discover > > > > > > > any motion of the earth relatively to the light medium, suggest that > > > > > > > the > > > > > > > phenomena of electrodynamics as well as of mechanics possess no > > > > > > > properties > > > > > > > corresponding to the idea of absolute rest. They suggest rather that, > > > > > > > as has > > > > > > > already been shown to the first order of small quantities, the same > > > > > > > laws of > > > > > > > electrodynamics and optics will be valid for all frames of reference > > > > > > > for which the > > > > > > > equations of mechanics hold good.1 We will raise this conjecture (the > > > > > > > purport > > > > > > > of which will hereafter be called the Principle of Relativity) to > > > > > > > the status > > > > > > > of a postulate, and also introduce another postulate, which is only > > > > > > > apparently > > > > > > > irreconcilable with the former, namely, that light is always > > > > > > > propagated in empty > > > > > > > space with a definite velocity c which is independent of the state of > > > > > > > motion of the > > > > > > > emitting body." > > > > > > > > Einstien, Electrodynamics of Moving Bodies (Introduction) > > > > > > > > This text describes Einstein's postulate that there is no preferred > > > > > > > inertial frame of reference. > > > > > > > > "If at the points A and B of K there are stationary clocks which, > > > > > > > viewed in the stationary system, are synchronous; and if the clock at > > > > > > > A is moved with the velocity v along the line AB to B, then on its > > > > > > > arrival at B the two clocks no longer synchronize, but the clock moved > > > > > > > from A to B lags behind the other which has remained at B ..." > > > > > > > > Einstien, Electrodynamics of Moving Bodies (Section 4) > > > > > > > > The text describes the time dilation of a clock that moves from point > > > > > > > A to point B. If there is no preferred frame of reference then it is > > > > > > > just as true to say that > > > > > > > the clock is viewed as part of a stationary system and the points A > > > > > > > and B are in a moving system which moves at velocity -v. The > > > > > > > conclusion that time for both systems can be dilated with respect to > > > > > > > the other system is paradoxical. > > > > > > > No, it's not paradoxical at all. > > > > > > It is paradoxical because time for both systems cannot be dilated with > > > > > respect to each other. > > > > > This is your assumption about what can and cannot be. > > > > No, it is a logical inference derived from Einstein's description of > > > time dilation and his postulate that there is not preferred frame of > > > reference. > > > No, I'm sorry, but that is not a good inference. > > Why can't you identify what is wrong with it then? > > > I don't have any idea > > how you conclude from his postulate about no preferred frame that time > > for both systems cannot be dilated with respect to each other. > > That isn't what I am saying. I'm saying that for time for both systems > to be dilated with respect to each other constitutes a paradox, No, it does not. I suspect that you believe that it is because you believe the statement made by relativity is that "moving clocks run slow". You hear this to mean that "Clock A is running slower than clock B, and clock B is running slower than clock A." You furthermore believe that, logically, "Clock A is running slower than clock B" necessarily implies that "Clock B is running faster than clock A" and hence the paradox arises with the combination of sentences "Clock B is running faster than clock A" and "Clock B is running slower than clock A." The problem, you see, is that the comic-book statement you are using as your launching point belongs in COLP's Oversimplified Relativity. Relativity doesn't make that statement as carelessly and loosely as you're using it. Instead, it makes a more precise statement about what it MEANS to say that Clock B is running slower than Clock A. And here is where identification of particular *events* comes into play. And this makes all the difference. PD > and > this situation arises when the idea that no preferred frame of > reference exists is applied to the example. Since we know from > experiment that time dilation is real, the only remaining assumption > is that of the non-existence of a preferred frame of reference; i.e > that assumption is false because it results in a paradox.- Hide quoted text - > > - Show quoted text -
From: Daryl McCullough on 6 Jul 2010 11:18 harald says... >The twin scenario was presented by Langevin in 1911 to show that >physical acceleration is "absolute", even more so with SRT than with >Newton's mechanics. What does that mean? As I said, proper acceleration (as measured by an accelerometer) is absolute, but coordinate acceleration is certainly not. >He argued that these absolute effects detect the ether (what you call >a "preferred frame"). If that's what he argued, then he was wrong. The fact that acceleration is measurable does not imply the existence of a preferred rest frame. Here's an analogy: A flat Euclidean plane has no notion of a preferred direction. Any direction is as good as any other. But it certainly has a notion of a *change* of direction. If you draw a path on the Euclidean plane, then you can unambiguously determine whether the line is straight or curved, because a straight line connecting two points is shorter than any curved line connecting the same two points. If you measure the lengths of two curves, you can determine which one is straight. A rest frame in Einstein's spacetime is analogous to a direction in Euclidean space. There is no preferred rest frame in spacetime any more than is a preferred direction in the Euclidean plane. But a *change* of rest frames is certainly detectable, in the same way that a change in direction is detectable in the Euclidean plane. >However, Einstein (1916) considered that the PoR of SRT has an >"epistemological defect", since it relates to a privileged group of >"spaces" that cannot be observed. And what he could not observe, he >called 'factitious'. In other words, he rediscovered Newtons' argument >but he found it unacceptable. He preferred to go the opposite route >and extended the PoR as follows: > >"The laws of physics must be of such a nature that they apply to >systems of reference in any kind of motion". >As a result, physical acceleration is, according to Einstein's GRT, >*relative* - which is just the contrary of what Langevin argued based >on his "twins" example of SRT. As I said, proper acceleration is definitely *not* relative, but coordinate acceleration trivially *is*. But proper acceleration is measuring acceleration relative to *freefall*. >It should not be surprising that this was not only very confusing for >bystanders (who already hardly understood the difference between the >two theories), but that it even looked like a contradiction I would like to hear any coherent explanation of why it looks like a contradiction. The bare statement "The laws of physics must be of such a nature that they apply to systems of reference in any kind of motion" is not a contradiction---on the contrary, it is nearly a tautology. You can always write the laws of physics so that you can use an arbitrary coordinate system. To derive a paradox from the twin thought experiment, you need to reason something like this: 1. There exists two coordinate systems, C1 and C2, such that the path of the traveling twin, as described in C1, is the same as the path of the stay-at-home twin, as described in C2. 2. Therefore, the predicted age of the traveling twin, computed using C1, must be the same as the predicted age of the stay-at-home twin, computed using C2. I don't see how 2 follows from the general principle of relativity, as expressed in the sentence "The laws of physics must be of such a nature, blah, blah, blah." From the latter, it follows that one can use either C1 or C2 to compute the ages of the two twins, but it *doesn't* imply that the ages will be the same. To be able to conclude that, you need to assume a very specific form for the laws of physics. -- Daryl McCullough Ithaca, NY
From: colp on 6 Jul 2010 16:03 On Jul 7, 3:07 am, PD <thedraperfam...(a)gmail.com> wrote: > > > I don't have any idea > > > how you conclude from his postulate about no preferred frame that time > > > for both systems cannot be dilated with respect to each other. > > > That isn't what I am saying. I'm saying that for time for both systems > > to be dilated with respect to each other constitutes a paradox, > > No, it does not. Yes it does. If a clock in a moving frame runs slow, then a clock in a stationary frame runs fast when viewed from the moving frame. If that were not the case then you would get paradoxical outcomes. > > I suspect that you believe that it is because you believe the > statement made by relativity is that "moving clocks run slow". Relativity makes a statement that means exactly the same thing. "If at the points A and B of K there are stationary clocks which, viewed in the stationary system, are synchronous; and if the clock at A is moved with the velocity v along the line AB to B, then on its arrival at B the two clocks no longer synchronize, but the clock moved from A to B lags behind the other which has remained at B ..." Einstien, Electrodynamics of Moving Bodies > You > hear this to mean that "Clock A is running slower than clock B, and > clock B is running slower than clock A." No, B only runs slower than A if there is no preferred frame of reference. > You furthermore believe that, > logically, "Clock A is running slower than clock B" necessarily > implies that "Clock B is running faster than clock A" and hence the > paradox arises with the combination of sentences "Clock B is running > faster than clock A" and "Clock B is running slower than clock A." O.K. > The problem, you see, is that the comic-book statement you are using > as your launching point belongs in COLP's Oversimplified Relativity. It's not a comic book statement any more than Einstein's statement that a moving clock lags behind a stationary clock is a comic book statement. > > Relativity doesn't make that statement as carelessly and loosely as > you're using it. There is nothing careless or loose about my statement. > > Instead, it makes a more precise statement about what it MEANS to say > that Clock B is running slower than Clock A. And here is where > identification of particular *events* comes into play. And this makes > all the difference. So why can't you say what the difference is if it exists? Some vague reference to "events" doesn't cut it.
From: PD on 6 Jul 2010 16:52 On Jul 6, 3:03 pm, colp <c...(a)solder.ath.cx> wrote: > On Jul 7, 3:07 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > I don't have any idea > > > > how you conclude from his postulate about no preferred frame that time > > > > for both systems cannot be dilated with respect to each other. > > > > That isn't what I am saying. I'm saying that for time for both systems > > > to be dilated with respect to each other constitutes a paradox, > > > No, it does not. > > Yes it does. If a clock in a moving frame runs slow, then a clock in a > stationary frame runs fast when viewed from the moving frame. If that > were not the case then you would get paradoxical outcomes. See below. It'd be a good idea to read my whole post before opening your yap. > > > > > I suspect that you believe that it is because you believe the > > statement made by relativity is that "moving clocks run slow". > > Relativity makes a statement that means exactly the same thing. No, it does not. See below. > > "If at the points A and B of K there are stationary clocks which, > viewed in the stationary system, are synchronous; and if the clock at > A is moved with the velocity v along the line AB to B, then on its > arrival at B the two clocks no longer synchronize, but the clock moved > from A to B lags behind the other which has remained at B ..." > > Einstien, Electrodynamics of Moving Bodies > > > You > > hear this to mean that "Clock A is running slower than clock B, and > > clock B is running slower than clock A." > > No, B only runs slower than A if there is no preferred frame of > reference. > > > You furthermore believe that, > > logically, "Clock A is running slower than clock B" necessarily > > implies that "Clock B is running faster than clock A" and hence the > > paradox arises with the combination of sentences "Clock B is running > > faster than clock A" and "Clock B is running slower than clock A." > > O.K. And this is part of your problem. > > > The problem, you see, is that the comic-book statement you are using > > as your launching point belongs in COLP's Oversimplified Relativity. > > It's not a comic book statement any more than Einstein's statement > that a moving clock lags behind a stationary clock is a comic book > statement. Not so. Einstein's statement included things that you have discounted. For example, he makes note of specific events, rather than just making the general statement that "moving clocks" run slow. Furthermore, he makes EXPLICIT mention of the statement that the clocks at points A and B are initially synchronized IN THE K FRAME. A contradiction would arise by making the clock at B the moving clock only if the clocks are claimed to be intially synchronized also in the K' frame -- but they are NOT, and this is the essential detail that you have missed. Yes, in the K' frame, the B clock runs slower than the A clock, but when A arrives at B, it is STILL behind the B clock because in the K' frame the clocks are not initially synchronized. There is no contradiction. The observation that when the clock from A arrives at B, the former is behind the latter is a completely consistent observation in both frames. > > > > > Relativity doesn't make that statement as carelessly and loosely as > > you're using it. > > There is nothing careless or loose about my statement. Yes, there is, and I've pointed it out to you repeatedly, and you are ignoring it, preferring to stick to your guns with COLPs Oversimplified Relativity. I agree that COLPs Oversimplified Relativity is contradictory and should be chucked. But relativity does not suffer from that problem. > > > > > Instead, it makes a more precise statement about what it MEANS to say > > that Clock B is running slower than Clock A. And here is where > > identification of particular *events* comes into play. And this makes > > all the difference. > > So why can't you say what the difference is if it exists? Some vague > reference to "events" doesn't cut it. And again, it would help if you would actually READ what relativity says in a book designed to TEACH relativity, rather than just sticking to COLPs Oversimplified Relativity and demanding that people have COR make sense to you. I've already told you what the statement about time dilation is in regard to events. If you've forgotten it, then please reread that. If you don't know what an "event" is to a physicist, then I suggest you look it up, and preferably someplace other than the Internut. PD
From: PD on 6 Jul 2010 16:56
On Jul 5, 12:04 am, colp <c...(a)solder.ath.cx> wrote: > On Jul 5, 7:31 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jul 3, 6:06 pm, colp <c...(a)solder.ath.cx> wrote: > > > > On Jul 4, 2:14 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Jul 3, 1:06 am, colp <c...(a)solder.ath.cx> wrote: > > > > > > On Jul 3, 3:03 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jul 1, 7:56 pm, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > On Jul 2, 2:21 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Jun 30, 5:47 pm, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > > > <quote> > > > > > > > > > > > > At best, all you've done is show the > > > > > > > > > > > fallacies or assumptions inherent in COLP's Oversimplified Relativity. > > > > > > > > > > What specific fallacies or assumptions? Quotes, please. > > > > > > > > > > Sure. You've used the statement from COLP's Oversimplified Relativity > > > > > > > > > that moving clocks run slow (which you've said is true even for blue- > > > > > > > > > shifted clocks), and you've used the statement that COLP's > > > > > > > > > Oversimplified Relativity makes no provision whatsoever for a > > > > > > > > > compression of time for a clock turning around. This immediately leads > > > > > > > > > to several paradoxes, and this is ample reason to chuck Colp's > > > > > > > > > Oversimplified Relativity. > > > > > > > > > </quote> > > > > > > > > > > The statement that "moving clocks run slow" isn't an > > > > > > > > > oversimplification, it is directly inferred from Einstein's > > > > > > > > > "Electrodynamics of Moving Bodies". > > > > > > > > > It IS an oversimplification. If you've inferred this from his 1905 > > > > > > > > paper, then you've oversimplified. > > > > > > > > No, inferring something from a paper does not constitute an > > > > > > > oversimplification. > > > > > > > It does if it's an oversimplification of what's presented in the > > > > > > paper! > > > > > > It isn't. Claiming that it is without showing why is of no value. > > > > > You aren't owed an education on a newsgroup, despite your taunts to > > > > the contrary. > > > > I'm not asking for an education, I'm pointing out that all you have to > > > defend you beliefs are hollow claims. > > > No, they are fully supportable claims. > > Wrong. The burden of proof is yours. You can't support them because no > such support exists. I'm sorry, but both sentences are wrong. Since it's been pointed out to you that your understanding of relativity is shallow and oversimplified, and since resources to correct that have been explicitly pointed at for you, then the burden is on YOU to correct that. If you have an erroneous understanding of something, you do NOT have the right to insist, "My presentation of it is correct, unless someone steps in and proves that it's wrong." No one owes you a convincing. The facts are not hidden. They are at your disposal. You either CHOOSE to correct your erroneous understanding or you CHOOSE not to. PD |