Preferred Frame Theory indistinguishable from SR
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From: Daryl McCullough on 7 Jul 2010 16:05 harald says... >On Jul 7, 6:02=A0pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: >> That the notion of "straight" versus "nonstraight" is *not* >> dependent on a coordinate system. > >It's definitely the case for "straight" trajectories, which are for >example straight relative to an inertial system but not relative to a >rotating system. That's mistaken. Whether a trajectory is straight (or unaccelerated) is *not* relative to a coordinate system. If it is straight, it is straight in all coordinate systems. What varies from coordinate system to coordinate system is the *equation* describing a straight path. For Cartesian coordinates, the path x(s), y(s) satisfies: (d/ds)^2 x = (d/ds)^2 y = 0 For non-cartesian coordinates, the equation of a straight path is more complicated. >I understand why he agreed to call the clock exercise a "paradox" and >an "objection" against his theory, His dialog was a response to critics. The fact that he responded doesn't amount to admitting the critics were right. He's explaining why they are *not* right. >which required to be solved. It appears that you still don't >understand why, And the fact that you can't give a coherent answer to the question: why is the twin paradox a consistency challenge for Einstein's generalized principle of relativity seems to me to mean that you don't understand why, either. >> >> The modern way of looking at it is that "inertial forces" are >> >> felt whenever the observer is accelerating *relative* to freefall. >> >> Einstein originally thought of the equivalence principle differently: >> >> He thought that an object accelerating in a gravitational field felt >> >> two different kinds of forces: (1) inertial forces due to acceleration= >, >> >> and (2) gravitational forces. These two forces canceled in the case >> >> of freefall. >> >> >??? I strongly doubt that. Reference please! >> >> I cannot find an online reference, but it occurs in a discussion >> by Einstein of his "elevator" thought experiment. > >As far as I remember, he held that an object accelerating in a >gravitational field feels no force at all; does it make a difference? Right. The modern explanation is that an object in freefall is *not* accelerating; it is moving inertially. Einstein's original explanation (if I'm remembering it correctly) was that the object feels *two* forces that cancel each other: A downward force due to gravity, and an upward "inertial" force. >> >Good, we are making progress. :-) >> >Einstein held that, as he put it, acceleration is "relative": >> >according to his theory we may just as well claim that the traveler is >> >*not* physically accelerated, contrary to Langevin's and your claim. >> >> No, you are confused. As I have said, there are two different notions >> of "acceleration": (1) proper acceleration (acceleration relative to >> the local standard for freefall) and (2) coordinate acceleration >> (acceleration relative to whatever coordinate system you are using). >> Einstein and I are in complete agreement that for the traveling >> twin, proper acceleration is nonzero, while coordinate acceleration >> is zero (using the appropriate noninertial coordinate system). So >> where is the disagreement? There is none. > >There is no disagreement on that point. What about the induced >gravitational field? That's just the ordinary inertial forces associated with an accelerated observer. Calling them a gravitational field is to remind you that in Einstein's theory, there is no difference between a gravitational force and inertial forces. They are both manifestations of accelerating relative to the local notion of freefall. >> >He thought to solve the problem by saying that at the turnaround >> >(according to the stay-at-home), the traveler may consider himself as >> >remaining in place against an induced gravitational field that >> >appears. >> >> And certainly he may, in the sense that he may choose a coordinate >> system in which he is always at rest. The notion of being at rest >> is relative to a coordinate system in relativity. > >He only may do so if his induced gravitational field can be held to >be, as his theory claims, "physical", and propagating according to the >same laws of physics as all other gravitational fields. And that is the case. It's important to distinguish "gravitational field" from "gravity". They aren't the same thing. There are two different phenomena at work in the modern view of gravity: (1) Spacetime is *curved* by matter. What this means is that at each point in spacetime, there is a local notion of "freefall" or "inertial motion". Curvature means that this notion varies from point to point, rather than there being a global notion of an inertial frame. (2) Acceleration relative to the local notion of freefall results in inertial forces. This effect is exactly like Newtonian physics, where acceleration results in inertial forces. The difference is that in Newtonian physics, there is a consistent *global* notion of freefall or inertial motion, while in General Relativity, freefall varies from place to place. For effect (2), there is no distinction between "gravitational force" and any other inertial force. They're all inertial forces due to acceleration relative to the local notion of freefall. There is no "propagation" of effect (2). If you start accelerating, you instantly feel inertial forces. Inertial forces don't propagate in any physical sense. On the other hand, effect (1) has a very definite dynamic to it, which is describe by Einstein's field equations. Curvature is influenced by the presence of mass/energy/momentum. >> If you are asking, not about General Relativity, but the General >> Principle of Relativity: that isn't a theory of physics, it is >> a heuristic, or a philosophical position, or metaphysics. It has >> no physical meaning, except to the extent that it guides us in >> coming up with better theories of physics. > >I rarely saw a more aggressive criticism against Einstein's >theory. :-) The generalized principle of relativity is not a theory. -- Daryl McCullough Ithaca, NY
From: colp on 7 Jul 2010 17:49 On Jul 8, 8:05 am, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > harald says... > > >On Jul 7, 6:02=A0pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > >> If you are asking, not about General Relativity, but the General > >> Principle of Relativity: that isn't a theory of physics, it is > >> a heuristic, or a philosophical position, or metaphysics. It has > >> no physical meaning, except to the extent that it guides us in > >> coming up with better theories of physics. > > >I rarely saw a more aggressive criticism against Einstein's > >theory. :-) > > The generalized principle of relativity is not a theory. Right. It is an assumption, and the application of that assumption leads to contradictions. This is a case of doctrinal annihilation; i.e. a set of postulates that are collectively inconsistent. The relevant postulates are: 1. There is not preferred frame of reference. 2. Moving clocks run slow. (Paraphrased from Einsteins "Electrodynamics of Moving Bodies") Since we know that moving clocks _do_ run slow, the only logical conclusion is that a preferred frame of reference exists. The assertion that a preferred frame of reference exists is a philisophical one, and points towards the epistemological schism of natural philosophy which led to the development of science (i.e. knowledge of the physical realm) and religion (i.e. beliefs about the theological realm) as separate disciplines.
From: colp on 7 Jul 2010 18:10 On Jul 7, 8:56 am, PD <thedraperfam...(a)gmail.com> wrote: > 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. Wrong again. Ei incumbit probatio qui dicit, non qui negat. The burden of the proof lies upon him who affirms, not he who denies. Dig. 22, 3, 2; Tait on Ev. 1; 1 Phil. Ev. 194; 1 Greenl. Ev. 74; 3 Louis. R. 83; 2 Dan. Pr. 408; 4 Bouv Inst. n. 4411. Is the fact that you can't show proof due to anything other than a refusal to admit that Einstein's first postulate of relativity is wrong?
From: PD on 7 Jul 2010 18:39 On Jul 7, 5:10 pm, colp <c...(a)solder.ath.cx> wrote: > On Jul 7, 8:56 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > 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. > > Wrong again. > > Ei incumbit probatio qui dicit, non qui negat. The burden of the proof > lies upon him who affirms, not he who denies. Dig. 22, 3, 2; Tait on > Ev. 1; 1 Phil. Ev. 194; 1 Greenl. Ev. 74; 3 Louis. R. 83; 2 Dan. Pr. > 408; 4 Bouv Inst. n. 4411. Sorry, but debate-club arm-wrestling stances do not elicit engagement just because you want it to be so. > > Is the fact that you can't show proof due to anything other than a > refusal to admit that Einstein's first postulate of relativity is > wrong? You are asserting it is wrong. Prove it. Burden is on you.
From: colp on 7 Jul 2010 18:43
On Jul 7, 8:52 am, PD <thedraperfam...(a)gmail.com> wrote: > 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: > > > 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. I haven't discounted them. > For example, he makes note of specific events, rather than just making > the general statement that "moving clocks" run slow. The description of the specific events only serves to illustrate that it is the moving clock that runs slow compared to the stationary clock. > Furthermore, he > makes EXPLICIT mention of the statement that the clocks at points A > and B are initially synchronized IN THE K FRAME. Assuming that they weren't synchonized in my general description of "the moving clock runs slow" would be arbitrary and illogical. Remember I was talking about _the_ clock, in reference to the moving clock described in "Electrodynamics of Moving Bodies", not to a clock in an arbitrary system. > 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. No, it isn't a missing detail, it is an implication of Einstein's first postulate of relativity. Here is Einstein's description of the clocks: "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 ..." Let us call the moving system K', in which the moving clocks at A' and B' are synchronized for an observer in K'. The stationary system K also has two clocks, but these two clocks are synchronized for an observer in K. Frames K and K' move at a constant velocity with respect to each other. If there is no preferred frame of reference then there is no reason why the clocks at A' and B' cannot also be synchronized for an observer in K', just as the clocks at A and B are for an observer in K, due to the symmetry of the two frames and their respective clocks. |