Albion wrote:
As I understand it, the faster I accelerate myself the slower time for
me moves as compared to an observer I left behind. Andromeda my be 2
million light years away but at higher and higher speeds accelerated to
I could get there in no time at all, but it would still be two million
years for the observer I left on earth. I also understand that if you
travel in a strait line eventually you will come back to where you
started. So given that, I could accelerate myself to some minute
fraction under the speed of light then coast and return to the place I
left in a few seconds. To the observer I left behind billions and
billions of years may have past making the universe to him that much
older but to me the universe would only be a few seconds older. How can
the universe be two different ages when I arrive back? Does
decelerating myself to the original speed I started at cause time to
speed up that much? Am I actually accelerating myself again to get back
to the speed of the original observer?

Both the "observer" and the universe at large will be equally older
when you finally return. The observer will have been dead for
millennia, many stars will have exhausted their nuclear fuel, galaxies
will have undergone whole rotations.

-Mark Martin