How can the MMx math be corrected?
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From: whoever on 13 May 2010 01:54 "Da Do Ron Ron" <ron_aikas(a)hotmail.com> wrote in message news:e1830739-517f-484d-84d7-6e5df36e4c92(a)h9g2000yqm.googlegroups.com... > ["Inertial" declared] >> There is no absolute rest > > Proof? Define what it means first > Here's my proof that there is: No such thing > Also, as I mentioned before, Einstein did not really state, much less > prove, that absolute motion does not exist, Only that it is no different to any other motion > but merely denied the > measurement or detection thereof. Which remains > (Einstein know well that absolute > motion certainly exists. Nope. SR removed the need for such a notion. Perhaps you are thinking of LET? > He stated so in ways such as this: > "For owing to the alteration in direction of the velocity of rotation > of the earth in the course of a year, the earth cannot be at rest > relative to the hypothetical system K0 throughout the whole year." That has nothing to do with absolute motion. Clearly you don't understand what was said. > Of course, the master relativist always hedges his bet by adding such > things as quotes or the word "hypothetical," but it is clear to > anyone > with half a brain that Einstein was speaking non-hypothetically of > the > dear Earth's absolute motion through space.)(Wheeler also mentioned > such motion in the same connection.) No .. he wasn't .. just any arbitrary inertial frame. > But Einstein was drastically wrong in claiming that we have no means > of detecting this absolute motion No .. he wasn't > because he overlooked the extremely > simple fact that light itself is an absolute frame. Light simply has speed c relative to every inertial frame. No inertial frame can be at rest in that 'frame'. The 'frame' for light isn't a rest frame, nor is it what is meant by 'absolute frame' > (It's speed in or > through space is fixed - no slowing - no speeding up - and it is a > known speed - so this means that any light ray in space is certainly > an absolute frame.) The speed of light is the same in all frames. There are an infinite number of such non-inertial frames associated with light. > [T Robts claimed] >>>> "length of an arm measured in frame S" means a measurement in frame S, >>>> and if S is moving relative to the arm then the value can be different >>>> from the proper length of the arm. > > [~RA~ merely enquired] >>> Why different? >>> (full details please) > > ["Inertial" also failed to answer] >> Read a real physics book > > For many who are reading this cute little thread, this quickie reply > perfectly masks the import of the quickie question, so "Inertial" did > his job properly (which was to evade the issue). I didn't evade anything > But why would "Inertial" wish to evade this issue? I don't > Because it goes quickly to the heart of the entire SR "length > contraction" > fiasco. you mean your lack of undersatnding of it > It would show that SR's "length contraction" is both trivial > and > useless to physics. Nope > It is of no more importance than the "size > shrinkage" > seen when two people depart. Wrong > And - even worse - it takes us away from > the > real issue of real (or absolute) length contractions, no such thing > the only kind > that can > explain the result of any real experiment, Wrong > including the MMx null > result. No shrinkage required and no SR contraction required. MMX happens in a lab frame . .the arms at rest in that frame, The light at rest in that frame. No need for any shrinkage or contractino. You do not understand SR. You do not understand MMx. You do not understand physics. --- news://freenews.netfront.net/ - complaints: news(a)netfront.net ---
From: Tom Roberts on 13 May 2010 01:58 harald wrote: > On May 11, 6:04 pm, Tom Roberts <tjrob...(a)sbcglobal.net> wrote: >> the best derivation of [SR's] equations has changed, because >> we have LEARNED A LOT since 1905 -- for instance, SR no longer depends in an >> essential way on electrodynamics or Maxwell's equations. > > As Einstein replaced Maxwell's equations by the second postulate, > original SR is already independent of Maxwell's equations. Not really. Einstein's 1905 second postulate explicitly refers to light, and that is electrodynamics, the classical theory of which is Maxwell's equations (and the theory Einstein used implicitly). > The "best" > derivation brings in the constant c through the back door; Nonsense, if by "c" you mean the speed of light (which in context appears to be what you mean). But "c" also means the invariant speed of the Lorentz transform, and OF COURSE that is "brought in" to SR, through the FRONT door. In the best derivation of SR I know, the second postulate is replaced with a postulate known as "causality" (but this is not the NAIVE "causality" that is all too often espoused around here): If a signal can be propagated from event P1 to event P2, then in any inertial frame t(P1) < t(P2) [here t(P) is the time coordinate of event P]. [The name comes from the fact that this implies that any cause precedes its effects in every inertial frame. One must of course include the PoR and the "hidden postulates" of SR in order to derive its equations. The derivation shows there is an invariant upper bound on signal propagation speed, notated as "c"; 1/c=0 corresponds to the Galilei group, but the value of 1/c is an EXPERIMENTAL issue, and it is found to be ~1/(300000000 m/s), not 0.] Where is the "back door" that "brings in" the speed of light? -- AFAICT the only way to do that is EXPERIMENTAL: the vacuum speed of light is observed to be equal to the invariant speed of the Lorentz transform (which is the only meaning of "c" in SR when derived in the above manner). That is not any kind of "back door" in a theory, it is relating constants of different theories to each other (here classical electrodynamics and SR). > if you > really think that that is an essential difference in theory, that > would be another reason to give it a different name. Hmmm. There is merit to that, but the community has not seen any need to change the name. This is partly because most textbooks still use the old postulates or variations of them -- those same textbooks then generalize the theory beyond it postulates, based solely on the generality of the PoR. Yes, physicists are often sloppy and lack rigor. > [my refusal to pander to ancient word meanings and notions] > DDRR is not going to get any > wiser from you. Of course not! To "become wiser" about SR he HIMSELF must STUDY; the internet is a very bad medium for that, and newsgroups like this are completely useless for it. Tom Roberts
From: whoever on 13 May 2010 01:58 "harald" <hvan(a)swissonline.ch> wrote in message news:5d13d6ae-81a5-439b-be21-a0f507e3141a(a)24g2000yqy.googlegroups.com... > On May 12, 12:09 am, Tom Roberts <tjrob...(a)sbcglobal.net> wrote: >> Inertial wrote: >> > [... statements I basically agree with ...] >> > Spacetime >> > itself takes on the characteristics of an aether without actually being >> > a 'substance'. >> >> No. What actually happens in SR/GR is that the geometry makes an aether >> superfluous -- if there were one it would be required to do absolutely >> nothing. >> IOW: the relevant "physical relationships" in LET are geometrical >> relationships >> in SR/GR. >> >> For instance, the "physical contraction" of moving rods and the >> "physical slowing" of moving clocks in LET become merely two >> aspects of geometrical projection in SR/GR. >> >> Remember the difference between world and model: spacetime is part of the >> model, >> while aether is putatively part of the world. Spacetime cannot "take on >> characteristics of an aether", because they are components of completely >> different realms. Spacetime cannot be considered to be the model of some >> aether, >> as it is just a manifold with metric (an associated geometry) -- it has >> no >> physical aspects with which to model a physical substance like aether. > > [...] > >> Tom Roberts > > Hi Tom, > > Not only what you call SR differs from the SRT of Einstein It doesn't > and > Lorentz, Lorentz didn't have SRT .. he had what we call LET. Very different (though the same results for what we measure .. different reasons for it) > also what you call GR differs from Einstein's GRT. But I > agree with you that spacetime does not have ether characteristics. It does in SR/GR. That reality behaves as per SR/GR means you get a propagation speed of light of c. That does not require some aether propagation medium. Same for everything else about aether .. it is all explained just nicely by physics without the need for introducing an aether. > Only what you call "model" and "world", I call "mathematical > description" and "physical model". So reality isn't real.. its just a model .. that's just nonsense. --- news://freenews.netfront.net/ - complaints: news(a)netfront.net ---
From: harald on 13 May 2010 09:39 On May 13, 7:58 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > harald wrote: > > On May 11, 6:04 pm, Tom Roberts <tjrob...(a)sbcglobal.net> wrote: > >> the best derivation of [SR's] equations has changed, because > >> we have LEARNED A LOT since 1905 -- for instance, SR no longer depends in an > >> essential way on electrodynamics or Maxwell's equations. > > > As Einstein replaced Maxwell's equations by the second postulate, > > original SR is already independent of Maxwell's equations. > > Not really. Einstein's 1905 second postulate explicitly refers to light, > and that is electrodynamics, the classical theory of which is Maxwell's > equations (and the theory Einstein used implicitly). > > > The "best" > > derivation brings in the constant c through the back door; > > Nonsense, if by "c" you mean the speed of light (which in context appears to be > what you mean). But "c" also means the invariant speed of the Lorentz transform, > and OF COURSE that is "brought in" to SR, through the FRONT door. > > In the best derivation of SR I know, the second postulate is replaced with a > postulate known as "causality" (but this is not the NAIVE "causality" > that is all too often espoused around here): > > If a signal can be propagated from event P1 to event P2, then in any > inertial frame t(P1) < t(P2) [here t(P) is the time coordinate of > event P]. > > [The name comes from the fact that this implies that any cause > precedes its effects in every inertial frame. One must of course > include the PoR and the "hidden postulates" of SR in order to > derive its equations. The derivation shows there is an invariant > upper bound on signal propagation speed, notated as "c"; 1/c=0 > corresponds to the Galilei group, but the value of 1/c is an > EXPERIMENTAL issue, and it is found to be ~1/(300000000 m/s), > not 0.] > > Where is the "back door" that "brings in" the speed of light? Original SRT *claims* ("predicts") that invariant c equals the vacuum speed of light. The replacement theory simply discovers by experiment that c corresponds to that value. > -- AFAICT the only > way to do that is EXPERIMENTAL [..] > > if you > > really think that that is an essential difference in theory, that > > would be another reason to give it a different name. > > Hmmm. There is merit to that, but the community has not seen any need to > change the name. Perhaps the difference is so small that few people would bother? > This is partly because most textbooks still use the old postulates > or variations of them -- those same textbooks then generalize the > theory beyond it postulates, based solely on the generality of > the PoR. Yes, physicists are often sloppy and lack rigor. > > [my refusal to pander to ancient word meanings and notions] > > DDRR is not going to get any wiser from you. > > Of course not! To "become wiser" about SR he HIMSELF must STUDY; the internet is > a very bad medium for that, and newsgroups like this are completely useless for it. It's only hopeless if he doesn't study any of the references. Regards, Harald
From: Da Do Ron Ron on 13 May 2010 15:31
On May 13, "whoever" whatever or Inertial wrote: > "Da Do Ron Ron" wrote in messagenews:e1830739-517f-484d-84d7-6e5df36e4c92(a)h9g2000yqm.googlegroups.com... > The speed of light is the same in all frames. Cite the experiment whereby light's speed between two clocks was measured. (no transported or rotating clocks because they can run slow) >> But Einstein was drastically wrong in claiming that we have no >> means of detecting this absolute motion > No .. he wasn't Show how light's speed between two clocks will be c in more than one inertial frame. (use only one light source to make sure that you have two different frames - otherwise, you will just be repeating a single-frame experiment) [T Robts claimed] >>>>> "length of an arm measured in frame S" means a measurement >>>>> in frame S, and if S is moving relative to the arm then the >>>>> value can be different from the proper length of the arm. [~RA~ merely enquired] >>>> Why different? >>>> (full details please) ["Inertial" replied] >>> Read a real physics book [~RA~] >> For many who are reading this cute little thread, this quickie reply >> perfectly masks the import of the quickie question, so "Inertial" >> did his job properly (which was to evade the issue). ["Inertial" aka "whoever"] > I didn't evade anything You are still evading because you did not answer the question. I firmly predict that you will never answer it. ~RA~ |