Re: Bell's Spaceship paradox


"Tom Roberts" <tjroberts137@xxxxxxxxxxxxx> wrote in message news:gYmAj.8972$tW.5201@xxxxxxxxxxxxxxxxxxxxxxx
Martin Hogbin wrote:
There seems to me to be an error in the Wikipedia
article. The two spaceships are described as having
the same proper acceleration. Later on it twice
claims that the distance between the ships remains
constant (by definition), as measured in the launch
frame. For this to be the case, the two ships would
need to have constant coordinate acceleration in the
launch frame.

If the two spaceships have identical proper acceleration profiles as a
function of their proper time, then they also have identical coordinate
acceleration profiles relative to the launch frame as a function of time
in the launch frame (they start simultaneously in the launch frame). For
this case the spaceships remain a constant distance apart in the launch
frame, when looked at simultaneously in the launch frame. All of this is
independent of the actual acceleration profile used, and it need not be
constant -- all that matters is that the same profile is used by both
spaceships.

Thanks Tom, that answers my question. Is there a simple way of
showing that? It does not seem obvious to me.


--
Martin Hogbin



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