De Sitter's experiment and the relative motion of photons with respect to the surface of the star
in [Relativity]
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From: Henry Wilson DSc on 2 Feb 2010 17:46 On Tue, 02 Feb 2010 22:12:34 +0000, tominlaguna(a)yahoo.com wrote: >On Tue, 02 Feb 2010 04:17:12 GMT, ..@..(Henry Wilson DSc) wrote: > >>On Mon, 1 Feb 2010 19:23:37 -0800 (PST), artful <artful_me(a)hotmail.com> wrote: >> >>>On Feb 2, 2:02�pm, ..@..(Henry Wilson DSc) wrote: >>>> On Mon, 1 Feb 2010 17:00:50 -0800 (PST), PD <thedraperfam...(a)gmail.com> wrote: >>>> >On Feb 1, 5:59�pm, train <gehan.ameresek...(a)gmail.com> wrote: >> >>>> >This is not what the principle of equivalence says. The principle of >>>> >equivalence makes NO claim that the "results" will be the same in >>>> >different inertial frames. This is KNOWN not to be true from the days >>>> >of Galileo. A ball falling from the top of the mast on a ship takes a >>>> >straight line path in the frame of a ship, but a parabolic path in the >>>> >frame of the shore -- two different "results" regarding the same >>>> >events as seen in two different frames. What the principle of >>>> >equivalence says is that the laws of physics are the same in all >>>> >inertial frames -- and a parabolic path and a straight line path are >>>> >both described by the very same laws of physics. >>>> ...but you still can't provide a logical physical reason as to why a light >>>> pulse should reflect at the same speed from two relatively moving mirrors. >>>> >>>> Henry Wilson... >>>> >>>> .......provider of free physics lessons >>> >>>The incident speed wrt the mirror is the same as the reflected speed >>>wrt the mirror. That is how mirrors work. Do you have a problem with >>>that? >> >>I don't...but Einstein obviously did. >> >>S-----p->c(wrt source)--------------|M1 >> |M2 v<- >> >>Let the pulse strike the two mirrors when they are adjacent. >>It closes on M1 at c and departs at c. >>It closes on M2 at c+v and departs at c-v. >>Strange, eh? >> >>I wonder how many fairies can dance on the surface of a mirror. >> >>>Then use velocity composition to work out how that speed will >>>be in another relatively moving inertial frame. Use vector addition / >>>subtraction to work out closing/separation speeds >> >>Hahahahhaaha! What kind of answer is this? >> >>Einstein's velocity composition equation is just another form of his P2. >>Look, I'll show you... >> >>Let w (the light speed in a frame moving at v) always be = c by postulate. >> >>w = c = c(c+v)/(c+v) = (c+v)/(1+v/c) = (c+v)/(1+vc/c^2) >> > >Great job on the equation, Henry! Keep it up. Thanks. But I'll let Einstein have all the credit... >>...can I have my Nobel now please...for being expert at sniffing out circular >>logic? >> >> >> >>Henry Wilson... >> >>.......provider of free physics lessons Henry Wilson... ........provider of free physics lessons
From: PD on 2 Feb 2010 17:59 On Feb 2, 2:21 pm, John Kennaugh <J...(a)notworking.freeserve.co.uk> wrote: > PD wrote: > >On Jan 31, 1:23 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > > >> De Sitter's argument supports many theories that consider the speed of > >> light to be source independent. Other experiments eliminate most of > >> them. To eliminate a theory you need to come up with an experiment > >> that contradicts a prediction of the theory. Since SR and LET share > >> the same math you can't eliminate one without also eliminating the > >> other. > > >This isn't quite so. SR makes predictions that LET does not, and > >that's because the *physical* foundations are different, though the > >math is common in their *common* experimental domain. > > What a load of waffle. > SR does not have any *physical* foundations it is a principle theory; a > mathematical model based on "empirical foundations" (AE). It is based > upon two postulates the first was thought not to apply to EM theory as > it was believed that every FoR was unique in that it had a unique speed > w.r.t Maxwell's aether. That was shown not to be the case as the sort of > experiment expected to show absolute speed dependency failed to do so. > The PoR which has its origins with Galileo I think was therefore > re-established empirically. The second postulate is a mixture of > > i) Maxwell's aether theory - which stated that the speed of light is > independent of the speed of the source because it is constant w.r.t the > aether. > > ii) The generally held view among Einstein's contemporaries was that the > MMX had shown that an observer has always zero speed w.r.t the aether. > The second postulate simply describes what an observer stationary w.r.t > the aether would observe. Einstein's attempts to convince others that he > was on to something *physical* in justification of the postulate in the > form of "an aether without the immobility of Lorentz's" (1920 lecture) > failed. Einstein's objection to Lorentz's theory was in respect of the > theoretical structure i.e. its physical interpretation and he totally > failed to come up with an alternative. Physicists decided that a physics > theory did not require a physical interpretation and accepted SR without > one. As the aether was part of the physical interpretation of Maxwell's > theory this decision also allowed physics to disown the aether and > describe a set of equations SR/Lorentz and Maxwell as a "theory". > > >Thus, experimental support for our model of the weak > >interaction is also support for SR, though not for LET > >For example, SR > >makes the statement that ANY interaction must be manifestly covariant, > >which includes, for example, the weak interaction. LET makes no claim > >like that. > > If you are talking of the theory as provided by Einstein then his theory > made no such claim either. But I did not say that. I said SR, which is a *living* theory, not one that came complete and in finished form in 1905. > All you are saying is that such a statement > has been added as a part of relativity but has not been added to LET. SR > is simply Lorentz's maths without the theory which went with it. That's incorrect. SR as it *presently* exists is a physical theory that has a *different* physical basis than LET. > > >. The converse > >is that if *any* interaction showed signs of violating covariance, > >then SR would be in some trouble, while LET would not necessarily be > >likewise. So the stakes are higher in that regard for SR. > > -- > John Kennaugh
From: Henry Wilson DSc on 2 Feb 2010 18:18 On Tue, 2 Feb 2010 14:51:12 -0800 (PST), artful <artful_me(a)hotmail.com> wrote: >On Feb 3, 7:17�am, ..@..(Henry Wilson DSc) wrote: >> Consider a vertical mirror moving towards a light source. >> >> S--------------------------v<--|M >> >> I challenge you to apply any of Einstein's equations to show that, in the >> mirror frame, the reflected and incident light speeds are the same. > >What sort of challenge is that? Pretty much trivial. > >SR says speed of light is c in every inertial frame .. so in frame of >mirror, incident speed is c and reflected speed is c. c == c. Done. Not done. You have merely restated P2. >If you really want, you can use the velocity composition formula to >convert the speed c in the S frame to c in the M frame. And if >incident speed is c, reflected speed is c. Is it? Why don't you show me how and why, eh? Show exactly how a closing speed of c+v and a separation speed of c-v in the source frame can translate into both speeds equalling c in the mirror frame. You are free to use any of Einstein's equations. Henry Wilson... ........provider of free physics lessons
From: eric gisse on 2 Feb 2010 18:52 ...@..(Henry Wilson DSc) wrote: > On Tue, 2 Feb 2010 14:51:12 -0800 (PST), artful <artful_me(a)hotmail.com> > wrote: > >>On Feb 3, 7:17 am, ..@..(Henry Wilson DSc) wrote: >>> Consider a vertical mirror moving towards a light source. >>> >>> S--------------------------v<--|M >>> >>> I challenge you to apply any of Einstein's equations to show that, in >>> the mirror frame, the reflected and incident light speeds are the same. >> >>What sort of challenge is that? Pretty much trivial. >> >>SR says speed of light is c in every inertial frame .. so in frame of >>mirror, incident speed is c and reflected speed is c. c == c. Done. > > Not done. You have merely restated P2. > >>If you really want, you can use the velocity composition formula to >>convert the speed c in the S frame to c in the M frame. And if >>incident speed is c, reflected speed is c. > > Is it? > > Why don't you show me how and why, eh? What would be the point of that? > > Show exactly how a closing speed of c+v and a separation speed of c-v in > the source frame can translate into both speeds equalling c in the mirror > frame. You are free to use any of Einstein's equations. > > > > Henry Wilson... > > .......provider of free physics lessons
From: Henry Wilson DSc on 2 Feb 2010 19:44
On Tue, 02 Feb 2010 15:52:11 -0800, eric gisse <jowr.pi.nospam(a)gmail.com> wrote: >..@..(Henry Wilson DSc) wrote: > >> On Tue, 2 Feb 2010 14:51:12 -0800 (PST), artful <artful_me(a)hotmail.com> >> wrote: >> >>>On Feb 3, 7:17 am, ..@..(Henry Wilson DSc) wrote: >>>> Consider a vertical mirror moving towards a light source. >>>> >>>> S--------------------------v<--|M >>>> >>>> I challenge you to apply any of Einstein's equations to show that, in >>>> the mirror frame, the reflected and incident light speeds are the same. >>> >>>What sort of challenge is that? Pretty much trivial. >>> >>>SR says speed of light is c in every inertial frame .. so in frame of >>>mirror, incident speed is c and reflected speed is c. c == c. Done. >> >> Not done. You have merely restated P2. >> >>>If you really want, you can use the velocity composition formula to >>>convert the speed c in the S frame to c in the M frame. And if >>>incident speed is c, reflected speed is c. >> >> Is it? >> >> Why don't you show me how and why, eh? > >What would be the point of that? To prove that there isn't a great hole in the consistency of SR as a mathematical theory... >> Show exactly how a closing speed of c+v and a separation speed of c-v in >> the source frame can translate into both speeds equalling c in the mirror >> frame. You are free to use any of Einstein's equations. >> >> >> >> Henry Wilson... >> >> .......provider of free physics lessons Henry Wilson... ........provider of free physics lessons |