Re: Einstein's lopsided caricature of space and time

russell@xxxxxxxx wrote:
> I haven't been following this thread, so my only aim here
> is to correct some errors you made.
>
> Thomas Smid wrote:
>
> > Now consider two bombs at a distance x from you at the moment when you
> > send out the light signal (t=0), one stationary, another moving away
> > with velocity v. Assume further that both bombs have clocks identical
> > to and synchronized with yours.
>
> Wait, this is ambiguous. Yes you can set the moving clock's
> t'=0 at the moment (in your frame) that your t=0, but there
> are two caveats to calling this a "synchronization":
> 1. It won't *stay* synchronized, since its time is dilated
> relative to yours.

You should probably read some of the previous posts (at least those by
Dirk and me). We are not at a stage of the discussion where can apply
any consequences of the Lorentz transformation as Dirk is still trying
to educate me how the Lorentz transformation is being derived in the
first place. So for the moment forget anything about time dilation and
length contraction. The only issue of relevance at this stage is a
consistent application of the invariance of the speed of light when
light signals are sent to a moving object.

Nevertheless, even if you can't rid yourself of the 'time dilation'
idea, the point here is that the arrival of the light signal is timed
for each bomb in its own respective frame, so if the light source is a
distance x away from either of them when the light signal is emitted,
both will receive the signal at time t=x/c *according to their
respective clock*. Now since the clock of the resting bomb is in the
same frame as the reference clock at the light source, you know
therefore that also according to the latter both bombs will have
received the signal (i.e. exploded) at the same time. However, the
bombs will be at different distances as the moving bomb will have
travelled a distance v*x/c while the light signal was on its way. Of
course, the optical information about the explosions will arrive back
at the light source at different times as the distances covered are
different, but this does not affect the fact that both bombs have
exploded simultaneously (given the circumstance that their initial
distance was identical) but in different locations (given the
circumstance that one bomb was moving. You could demonstrate this for
instance by putting synchronized clocks in the inertial frame all the
way along the distance scale and would find that the resting bomb
knocks out the clock at distance x at time t=x/c and the moving bomb
knocks out the clock at distance x*(1+v/c) also at time t=x/c (and as
argued above already, the clocks on both bombs also will be stopped at
time t=x/c).

Thomas

.

Relevant Pages

  • Re: Einsteins lopsided caricature of space and time
    ... >>> Now consider two bombs at a distance x from you at the moment when you ... > light signals are sent to a moving object. ... Now since the clock of the resting bomb is in the ...
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  • Re: Einsteins lopsided caricature of space and time
    ... >>> obviously would find a distance of zero for all the events ... > 1B) I have a clock in my hand and a flashlight. ... > event of reflection of the signal on my TV is 1/2 c, ... that the equation is in fact wrong if applied to light signals (as I ...
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  • Re: Einsteins lopsided caricature of space and time
    ... >>> obviously would find a distance of zero for all the events ... > 1B) I have a clock in my hand and a flashlight. ... > event of reflection of the signal on my TV is 1/2 c, ... that the equation is in fact wrong if applied to light signals (as I ...
    (sci.physics.relativity)
  • Re: Distance-dependent time contraction
    ... This event takes place at distance ... Your light signal was emitted at time ts1 (on your clock), ... to the one with the clock and the signaling gear) if t1 = t2. ... and your light signals. ...
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  • Re: Einsteins lopsided caricature of space and time
    ... >> time units are defined by other means than light signals (otherwise we ... >> Now consider two bombs at a distance x from you at the moment when you ... > seems there is some misunderstanding between you and Dirk ... there might have been a slight misunderstanding ...
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