sci.physics.research

The links cited don't describe a paradox at all, just an incompletely
stated
question.

If the two ships accelerate but remain at rest in the same inertial
frame,
then the distance between them in that rest frame will not change.

If the frame (= both ships) is accelerated, then the distance between
them in
the frame with respect to which they are being accelerated will
decrease,
by the Lorentz formula. In their rest frame, the distance will not
change.

The "paradox" is because Newtonian absolute space is being assumed
without
thought of its relativistic implications. There is no such thing as
"distance",
unless one stipulates an inertial frame in which it is to be measured.

Adding energy to an object in an inertial frame causes that object to
be contracted in space and time in that frame, making general
relativity
an implication (integration) of special relativity.

jacques wrote:
> This famous paradox is about the distance between two identicaly
> accelerating rockets starting from rest from an inertial lab frame. It
> is described in:
>
> /home/baez/physics/Relativity/SR/
> /wiki/Bell's_spaceship_paradox
>
> It illustrates the problem of defining a "physical"distance (something
> we would call"proper distance") in non inertial frames due to the
> breakdown of simultaneity.
>
> There is not only one definition and they do not give always the same
> result:(which one is correct?).
>
> In the Wiki article, one tries to avoid the difficulty in considering
> that the two rockets will stop their engine after the same ellapsed
> proper time continuing flight in inertial frames. So one can perform
> easily the distance "d" between rocket 1 and 2 in lab frame and this
> distance "D" in rocket 1 frame using plain Lorentz transform group.
> The result is that (D = d* gamma) which looks fine, but the conclusion
> looks quite odd to me, as it is said that a string linking the 2
> rockets should break according to this formula.
> I thought that, in SR, the Lorentz "contraction" between two inertial
> systems was not physical and would not involve the string to break.
> Can someone help me to understand whether and in case where I am
> wrong?
>
> Notice also that this solution does not describe the situation when
> the 2 rockets are accelerating, but the result of such situation when
> freezed..