Basic postulates of SR
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From: rambus2005 on 8 Aug 2006 03:28 Tom Roberts wrote: > Harry wrote: > > "Tom Roberts" <tjroberts137(a)sbcglobal.net> wrote in message > > news:V80Bg.4398$gY6.3733(a)newssvr11.news.prodigy.com... > >> Sergey Karavashkin wrote: > >>> We will study the basic postulates of special theory of relativity: the > >>> postulate of constant speed of light in all reference frames [...] > >>> Tom Roberts wrote: > >>>>that is not at all a postulate of SR. <shrug> > >>> It was Einstein himself who has > >>> introduced the term "L-postulate". > >> I repeat: anyone who can READ would avoid your error. Just go back and > >> actually READ Einstein's 1905 paper. He does not use what you claim is a > >> postulate, he formulates his postulate in a significantly different way. > >> <shrug> > > > > Although I tend to agree with you on this point, a number of physicists > > happen to disagree and read it roughly the way Sergey reads it. It's > > ambiguous for sure. > > This is not ambiguous in the least. Einstein's second postulate is > significantly different from what Sergey claimed above. There is > absolutely no doubt: > > 2. Jeder Lichtstrahl bewegt sich im <<ruhenden>> Koordinatensystem > mit der bestimmten Geschwindigkeit V, unabhaengig davon, ob dieser > Lichtstrahl von einem ruhenden oder bewegten Koerper emittiert ist. > -- A. Einstein, Ann. d. Physik, 4.17, p891-921 (1905). > > In English: > > 2. Every light ray moves with the precise speed c relative to the > "stationary" coordinate system, independent of whether the ray is > emitted by a stationary or moving source. > [translation mine, using modern terminology. Note that earlier > in the paper he defined "stationary system" as any specific > inertial frame (again, I'm using modern terminology here).] > > Nobody who actually reads Einstein's paper will claim that Einstein's > second postulate is anything at all like Sergey claimed above. <shrug> > > I'm not talking about the subtleties of translation (e.g. > in this usage is "bestimmten" best translated as > "determined", "definite", "certain", or "precise"?). > I mean the basic content of the postulate. > > Yes, numerous textbooks use alternate derivations of the equations of > SR, including significantly different statements of the second > postulate. That does not change what Einstein actually wrote. As for any > mathematical theory, there are many different sets of postulates that > lead to the same theory. But if, as Sergey said, "We will study the > basic postulates of special theory of relativity", then it is necessary > to get them right. Accurate scholarship IS important. <shrug> > > > Tom Roberts Tom, I think that you guys are wasting your time by taking this joker seriusly. He has a long history of idiotic papers, I think DirkVan can give you a "reference" on him. He's the mathematician who claims that he has proof that curl(grad(f)) is sometimes not zero.
From: Sergey Karavashkin on 8 Aug 2006 10:20 Sorcerer пиÑ?ал(а): > Okay... > .......... > Androcles. Dear Androcles, Iâ??m so glad to see our mutual intention to bring our positions together. As you have touched Michelson whom we discussed some time ago, let us finish this point. I would say, the site with a moving diagram of MMX is very nice, but nothing except this. See, what the problem is. Please take a sheet of paper, draw two frames, direction of wind in the axis x and instruments in two frames. Now start building rays. They to be perpendicular to each other in the moving frame, it is clear that in the stationary frame the transverse ray has to be a bit inclined. Correct? Well, we have drawn rays and converged them onto the ocular of microscope. Next, we changed the windâ??s direction by 90 degrees. Now the longitudinal ray became transverse and vice versa. But the initial adjustment of the instrument is unchanged and the longitudinal ray goes not horizontally but with an inclination that we chose when it went transversely to the windâ??s motion. But if in previous case this angle was compensated by the frameâ??s motion, now it is not, and the ray will go not horizontally but under same angle partially changed by the compensation of the transverse component of speed. And consider the transverse ray that was longitudinal. It had not an inclination angle in the stationary frame. This angle was unnecessary in passing to the moving frame. When it became transverse after the turn of instrument, now it has to gain this angle to be strongly transverse with account of instrumentâ??s motion. But we did not new adjustment, so in the moving frame it will gain an angle of inclination inverse to the angle which the transverse ray had in the stationary frame before turning. This is easy to draw it and I think, you already have it done. Let us see our result. It appears, if before turning the rays in the moving frame were strongly perpendicular to each other, after the turn a new longitudinal and new transverse rays are already not strongly perpendicular. Naturally, they will not converge at a common point. Other rays with other paths within the interferometer will converge at this point. And this is far from being all. I guess, you are aware of lasers and of interference on lasers. You perfectly understand, the interference to be possible, the between-rays convergence angle has to be non-zero. This angle can be least, as the wavelengths are also small, but the minutes of this angle basically change the interference pattern. This angle has an effect on the length of path of the ray in the interferometer. Draw the ray under an angle and you will see, it will reflect from the semi-opaque mirror not at the point which Michelson calculated. This means the change of length of paths. And if the rays begin â??runningâ?? over the mirror with the turn of interferometer (which is unavoidable with the said), there will begin the changes of mutual phases and change of elementary rays interfering at the specific point of screen. As Righy showed in 20th of past century, the mutual shift of rays and change of path lengths are directed oppositely, i.e. to compensate the shift of fringes. The MMX reference that you gave me disregards this all, so it is no more than a toy. >From the said it follows, the scheme on whose basis Lorentz and Fitzgerald have calculated their contractions and on which you rely is incorrect. The complete scheme is basically other. So let us start the account of arguments and facts from this point. And let the rockets fly meanwhile. :) Sergey
From: Sergey Karavashkin on 8 Aug 2006 15:36 Tom Roberts пиÑ?ал(а): > Harry wrote: > > "Tom Roberts" <tjroberts137(a)sbcglobal.net> wrote in message > > news:V80Bg.4398$gY6.3733(a)newssvr11.news.prodigy.com... > >> Sergey Karavashkin wrote: > >>> We will study the basic postulates of special theory of relativity: the > >>> postulate of constant speed of light in all reference frames [...] > >>> Tom Roberts wrote: > >>>>that is not at all a postulate of SR. <shrug> > >>> It was Einstein himself who has > >>> introduced the term "L-postulate". > >> I repeat: anyone who can READ would avoid your error. Just go back and > >> actually READ Einstein's 1905 paper. He does not use what you claim is a > >> postulate, he formulates his postulate in a significantly different way. > >> <shrug> > > > > Although I tend to agree with you on this point, a number of physicists > > happen to disagree and read it roughly the way Sergey reads it. It's > > ambiguous for sure. > > This is not ambiguous in the least. Einstein's second postulate is > significantly different from what Sergey claimed above. There is > absolutely no doubt: > > 2. Jeder Lichtstrahl bewegt sich im <<ruhenden>> Koordinatensystem > mit der bestimmten Geschwindigkeit V, unabhaengig davon, ob dieser > Lichtstrahl von einem ruhenden oder bewegten Koerper emittiert ist. > -- A. Einstein, Ann. d. Physik, 4.17, p891-921 (1905). > > In English: > > 2. Every light ray moves with the precise speed c relative to the > "stationary" coordinate system, independent of whether the ray is > emitted by a stationary or moving source. > [translation mine, using modern terminology. Note that earlier > in the paper he defined "stationary system" as any specific > inertial frame (again, I'm using modern terminology here).] > > Nobody who actually reads Einstein's paper will claim that Einstein's > second postulate is anything at all like Sergey claimed above. <shrug> > > I'm not talking about the subtleties of translation (e.g. > in this usage is "bestimmten" best translated as > "determined", "definite", "certain", or "precise"?). > I mean the basic content of the postulate. > > Yes, numerous textbooks use alternate derivations of the equations of > SR, including significantly different statements of the second > postulate. That does not change what Einstein actually wrote. As for any > mathematical theory, there are many different sets of postulates that > lead to the same theory. But if, as Sergey said, "We will study the > basic postulates of special theory of relativity", then it is necessary > to get them right. Accurate scholarship IS important. <shrug> > > > Tom Roberts Dear Tom, I hardly can understand you. You first claimed that there are no postulates in SR. Now you are writing: << Einstein's second postulate is significantly different from what Sergey claimed above >> Meanwhile we donâ??t discuss with you the formulation of postulates and we did not give it in our paper. Meanwhile we discuss with you only the fact of existence of postulates. Of which my incorrect opinion in German and English versions of postulate are you speaking? :) Sergey
From: Tom Roberts on 8 Aug 2006 21:20 rambus2005(a)yahoo.com wrote: > Tom, > I think that you guys are wasting your time by taking this joker > seriusly. Perhaps. Around here I take everyone seriously until they prove they are not serious. To me that is the only fair thing to do. Tom Robrts
From: Tom Roberts on 8 Aug 2006 21:24
Sergey Karavashkin wrote: > Tom Roberts ?????(?): >> 2. Jeder Lichtstrahl bewegt sich im <<ruhenden>> Koordinatensystem >> mit der bestimmten Geschwindigkeit V, unabhaengig davon, ob dieser >> Lichtstrahl von einem ruhenden oder bewegten Koerper emittiert ist. >> -- A. Einstein, Ann. d. Physik, 4.17, p891-921 (1905). >> In English: >> 2. Every light ray moves with the precise speed c relative to the >> "stationary" coordinate system, independent of whether the ray is >> emitted by a stationary or moving source. >> [translation mine, using modern terminology.] >> Nobody who actually reads Einstein's paper will claim that Einstein's >> second postulate is anything at all like Sergey claimed above. <shrug> > > Dear Tom, I hardly can understand you. You first claimed that there are > no postulates in SR. I have never said that. Perhaps your reading of English is not fluent. That's why I quoted the original in German. > Now you are writing: > << Einstein's second postulate is > significantly different from what Sergey claimed above >> Yes. Just look above to see that is true. <shrug> > Of which my incorrect opinion in > German and English versions of postulate are you speaking? Your wording of the postulate is SIGNIFICANTLY different in meaning from both Einstein's original and my translation. <shrug> Tom Roberts |