🚀 go-pugleaf

tolman%mindblow.cs.utah.edu@cs.utah.edu (Kenneth Tolman) writes:
:   A frame of reference moving very very fast has a time dilation, correct?
: (That is, if we are still and looking at someone moving they are "slow")
: When we look out into the universe- all galaxies are moving away from us,
: and the very far away galaxies are moving near the speed of light.
: 
: Therefore, THEIR TIME HAS BARELY BEGUN.  Their civilization's have not 
: started, and they live in a "young" universe.  Thus, if we could travel
: faster than light, we could jump backwards and live this whole universe
: through once again.  Of course, the converse is true just as well from
: their perspective.  Is this analysis somewhat correct?
: 

Excerpts from netnews.sci.physics: 30-Sep-92 Re: Make time stop? Mcinnes
B T @nuscc.nus.s (731)

> 				No.

Oh, be a little nice. IF you assume FTL travel, it *is* true; SR says
that FTL is equivalent to time travel, for just about this reason. 

To be accurate, SR says that a pair of events separated by a spacelike
interval in one reference frame will have an undefined ordering; which
comes "first" will depend on your reference frame. Thus, anything that
looks like FTL (jumping from the first event to the second) will look
like time travel from another reference frame. 

Andromeda is moving away from us; assume that space-time is flat, and it
passed us a billion years ago (by our clocks.) If you consider an event
whose position is there and whose time is "now" (using our local
definition of "now" and the coordinate system of our ref. frame), that
event will be in the past (in the sense that that event will have
experienced less than a billion years, Andromeda time, since the
galaxies passed.)

Of course, this all shows the meaninglessness of "now" more than
anything else, but it does demonstrate all the problems that Star Trek
blithely warps over. :-)

--Z

"And Aholibamah bare Jeush, and Jaalam, and Korah: these were the borogoves..."