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Absolute simultaneity with Einstein synchronized clocks?

  1. Jun 5, 2008 #1
    1. Absolute simultaneity with standard synchronized clocks
    In an one space dimensions approach we propose the following scenario. At the origin O of the inertial reference frame I we find a clock C0(0) and a source of light S(0). An observer R’ moves with constant speed V in the positive direction of the OX axis. M(a(xa) represents his position when source S emits a light signal in the positive direction of th)e OX axis, clock C0 reading t=0. M represents the location of R’ when the light arrives at the former position of R’ his position being defined by
    x=x(a)(1+V/c) (1)
    Clock C(x) reads at that very moment
    clocks C0 and C being standard synchronized.
    It is usual to consider that M(a) represents the apparent position M representing the actual position. (Robert J. Deissler, "The appearance, apparent speed and removal of optical effects for relavitistically moving objects," Am.J.Phys. 73 663 2005)
    The event E(x=xa(1+V/c); t=ta(1+V/c)) has when detected from I’ the space-time coordinates
    x'=x(a)/g (3)
    t'=t(a)/g . (4)
    Is there some flow?
  2. jcsd
  3. Jun 7, 2008 #2
    The set up seems extremely confused or at least incomplete.

    What is “a”
    “M(a(xa) “ looks like a typo.

    Can we assume x’=0 is where the observer R’ is at on I’
    When t=? & t’=? did R’ crossed x=0 sometime before the light flashed.
    The light flashes at x=0 t=0; where and when does it go off in the I’ frame.
    Since the source could be a point in the I’ frame. Where and when is that I’ frame point, x=? & t= ? when R’ was at x=0.

    I don’t know what the question “Is there some flow?” means;
    But I don’t see any prospects for setting any form of “Absolute Simultaneity” in this description.
  4. Jun 7, 2008 #3


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    I don't think I have ever understood one of Bernard's questions.
  5. Jun 16, 2008 #4
    apparent and actual positions

    Thanks for your answer. Consider please the following one space dimensions detected from I. A particle moves with constant speed V in the positive direction of the OX axis. x defines its position at t=0 when a light signal is emitted from the origin O (APPARENT POSITION) X defining its position when the light signal arrives at its location. (ACTUAL POSITION). We have
    X=x+Vx/c=x(1+V/c) (1)
    Let t=x/c and T=X/c be the times when the light signal arrives at the apparent and at the actual positions respectively. The mentioned light signal performs the synchronization of the clocks of I. Performing the Lorentz transformations to the rest frame of the moving particle I'
    we obtain
    T'=g(T-Vx/c^2)=T[(1-V/c)/(1+V/c)]^1/2=t/g (2)
    X'=g(X-VT)=X[(1-V/c)/(1+V/c)]=x/g (3)
    Do you consider that (2) and (3) are the transformation equations for the events e(x,x/c) and E(X,X/c) for the space-time coordinates of events associated with the apparent and the actual positions of the same particle? Is (2) an expression for absolute simultaneity (t=0, T'=0)
    The inertial reference frames I and I' are in the standard arrangement.
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