Joan-Claude van Dirk Helps to Trivialize Special Relativity
in [Relativity]
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From: Bilge on 17 Mar 2005 13:39 Harry: >"PD" <pdraper(a)yahoo.com> wrote in message >news:1111075406.192734.177260(a)g14g2000cwa.googlegroups.com... >> >> The difficulty with this, SR holds, is: >> 1. Given two observers in relative motion, there will be a disagreement >> as to whether two events are simultaneous or not. There is no physical >> way to determine which observer is correct. > >That is not a problem for SRT, just as it doesn't matter for Newtonian >mechanics not to know which observer is moving, and as it doesn't matter for >electronics not to know which conductor is at zero potential. One may just >assume whatever and it works. Pay attention, harry. Your reply has absolutely nothing to do with what he just said. And yes, it does matter whether or not two observers agree or disagree which events are simultaneous. If simultaneity is absolute, then two observers will _always_ agree on which events are simultaneous, in which case relativity would be wrong. Relativity can only be correct if simultaneity is not absolute. [This has been experimentally tested, by the way, in bell type experiment using moving beam splitters. It was found that there existed no intrinsic time ordering of spin measurements made over a spacelike interval. That doesn't mean that there could have been an intrinsic time ordering in some frame - their objective was to test exactly that - the existence of a preferred frame in order to salvage bohm's theory which requires such a frame.] >> 2. Given a set of observers all in relative motion and three events A, >> B, C, it will be the case that A and B will be simultaneous to only one >> observer among the set of observers, and B and C will be simultaneous >> to only one observer among the set observers, and these two observers >> will not necessarily be the same observer. The association of >> simultaneity with the observer-independent reality (i.e. absolute >> simultaneity) would imply that one of these choices is correct, > >Exactly, And the aforementioned experiment shows that there is no ``correct choice.'' Events which are simultaneous in one frame are simultaneous in _every_ frame. By definition, simultaneous events aren't time ordered. If events are time ordered, then their separation is timelike, not spacelike. Knock off the semantics dance. >> which >> would mean there would have to be a way to physically distinguish that >> choice as being correct (and the other incorrect). > >Certainly not, that's an erroneous argument. It's a perfectly valid argument. If one choice defined a time ordering, then every event in that frame wold be time ordered, in which case, the separation between the events would be timelike, not spacelike and the transforms would be the galilean transforms. >Why on earth would one think that whatever exist must be measurable >in principle, or worse, that it must be measurable with our existing >instruments? You who have suddenly become a philosopher ought to be able to grasp the reason why. Anything which can have any effect on anything in this universe, has to be measureable in principle, since by definition, an effect is the outcome of an experiment. Explain how something can affect physical objects, yet conspire to not affect the physical objects of an experiment. Does nature say, ``Uh oh, there's an experiment, time to make the effect disappear.'' Or perhaps, our instruments are constructed with materials from another universe, so that effects that really happen to planets and atoms don't affect our ``special'' instruments? Or possibly, god intervenes to render our experiments useless in discovering anything that you've prayed can't be ruled out by failing to measure it. >> 3. No test has been able to distinguish which choice is correct. > >Correct, AFAIK. Incorrect. The article below reports an experiment that demonstrates quantum correlations over a spacelike interval using moving beam splitters, are completely independent of any time ordering assigned to the measurements over that spacelike interval. A. Stefanov, H. Zbinden, N. Gisin and A. Suarez. Physical Review. A, volume 67, 042115 A related article is available at the arxiv: quant-ph/0311004
From: Dirk Van de moortel on 17 Mar 2005 13:57 <cadwgan_gedrych(a)yahoo.com> wrote in message news:1111076991.427191.250880(a)l41g2000cwc.googlegroups.com... > Dirk Van de moortel wrote: > > <cadwgan_gedrych(a)yahoo.com> wrote in message > news:1110999070.611006.230190(a)l41g2000cwc.googlegroups.com... > [snip] > > > > This proves that relativity's time dilation cannot pertain > > > to physical clock rhythms (or to any other processes > > > involving physical time or physical aging) > > > Time dilation pertains to physical measurements. > > Physics pertains to physical measurements. > > But we told you this before. > > The 3-clock "paradox" does not pertain to mere > measurements. Its two directly-compared clocks > show different times after being synchronous. > > But of course, this is why you cowardly snipped > my 3-clock "paradox" example. > > You can run, but you can't hide, from the truth. You can run, but you can't hide, from your immense stupidity Dirk Vdm
From: cadwgan_gedrych on 17 Mar 2005 14:04 PD wrote: > cadwgan_gedrych(a)yahoo.com wrote: [snip] > > Why don't you tell us how SR can correctly measure the length of > > even a rod that is at rest wrt our frame? > > > > In fact, why don't you tell us how SR can even correctly measure > > the one-way, two-clock speed of anything? > > > > In order to do that, here are the hurdles which SR must overcome: > > > > [1] SR must prove that its clocks are correctly synchronized. > > [2] SR must prove that its clocks are not physically slowed. > > [3] SR must prove that its rulers are not physically contracted. What happened to your defense of relativity?
From: Dirk Van de moortel on 17 Mar 2005 14:11 <cadwgan_gedrych(a)yahoo.com> wrote in message news:1111082696.603004.97190(a)z14g2000cwz.googlegroups.com... > PD wrote: > > cadwgan_gedrych(a)yahoo.com wrote: > [snip] > > > Why don't you tell us how SR can correctly measure the length of > > > even a rod that is at rest wrt our frame? > > > > > > In fact, why don't you tell us how SR can even correctly measure > > > the one-way, two-clock speed of anything? > > > > > > In order to do that, here are the hurdles which SR must overcome: > > > > > > [1] SR must prove that its clocks are correctly synchronized. > > > [2] SR must prove that its clocks are not physically slowed. > > > [3] SR must prove that its rulers are not physically contracted. > > What happened to your defense of relativity? What on earth makes you think it would *need* a defense? Ten years of your pathetic failures to understand the coordinate concept? I don't think anyone is here to defend it. We are here to help the confused. And to riducule the arrogant ignorants. Documentation? http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:brian+author:jones http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:martin+author:miller http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:ron+author:aikas http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:roy+author:royce http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:adward+author:travis http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:john+author:reid http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:gadwgan+author:gedrych http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:srdude http://groups-beta.google.com/groups?q=%3Asci.physics.*+author:2ndpostulatedude and counting. Dirk Vdm
From: Bilge on 17 Mar 2005 14:51
PD: >For a long time, folks were sure that neutrinos were massless and >left-handed. Couple of comments. Actually, most people only assumed that to the extent that no one had ever measured the mass definitively to be different from zero. Since I spent my graduate career doing experimental weak interaction physics, I can at least state that everyone I came in contact with was fairly unsure and were quite interested in neutrino oscillation experiments and right-handed weak currents. The standard model assumed massless neutrinos for similar reasons. It was the minimal higgs model that could be constructed and lacking empirical evidence to the contrary, I think there was just no reason to develop the model with a particle spectrum that more complex than was dictated. On the other hand, the neutrino mass has been the subject of speculation for as long as the neutrino has been known to exist. >As such, right-handed neutrinos would interact with >*nothing* in the universe and would, by their very nature, be >undetectable and would have no implications for the rest of reality. So >it was perhaps interesting to ask the question whether right-handed >neutrinos could exist *anyway*. The dominant thinking has been, of >course they *could*, but they are not part of physics. That is, to some extent, questionable. For example, every weakly interacting particle _except_ for the neutrino, is detectable by a parity conserving interaction. However, neutrinos are not, so if you perform a lorentz boost such that you change the helicity of the neutrino, of what hamiltonian is the neutrino and eigenstate, such that it can be measured? A right-handed weak interaction has been ruled out for a rather significant portion of the parameter space of W_R mass and mixing angle. The W_R mass can't be smaller than something like 400 GeV. The best value on the michel parameter, \rho is exactly 0.75 to four significant figures. The renormalization of the mass would also seem to be difficult to do when the right-handed component doesn't interact with itself. In lieu of any other interaction, the only thing left that could define the mass eigenstates, would seem to be gravity. |