From: news@sifon.cc.mcgill.ca
Newsgroups: rec.arts.startrek.tech
Subject: Re: Not the Technical Manual
Date: 17 Nov 92 19:31:31 GMT
Organization: McGill University

In article <8738@dirac.physics.purdue.edu> hinson@bohr.physics.purdue.edu (Jason W. Hinson) writes:
>CXMP@MUSICA.MCGILL.CA (CXMP) writes:
>
><6) CAUSALITY VIOLATION
><
><Jason Hinson regularly sermonizes on the net about the fact that faster
><than light travel normally causes causality violation.  Causality is the
><postulate that causes always preceed effects. If causality were violated
><then events could occur spontaneously with their cause revealed only
><after the fact. The possibility of causality violation would, of course,
><make it difficult for one to predict future events.  That faster than
><light travel can bring about causality violation is, of course, not
><immediately obvious until one does a mental experiment analogous to the
><one Einstein did with trains and lightening.
><
>(Stuff deleted)
>
><Jason Hinson points out, however, that if faster than light travel were
><made possible by a special frame of reference then this causality
><violation is avoided because the concepts of simultaneity and
><instantaneity could be defined with respect to this special frame.
>
>(Stuff deleted)
>
><Unfortunately, or fortunately depending upon your point of view,
><causality is also violated when one travels backward in time since
><one's arrival in the past is not something that can be predicted.  In
><addition to the time travel accomplished by the Enterprise via the
><Slingshot Effect and by "cold starting the warp drive" (TOS:"The Naked
><Time"), the original series allowed for time travel in "The City on the
><Edge of Forever", "The Alternative Factor" and "All our Yesterdays".
><The Next Generation, meanwhile, had "time vortices" in "Time Squared"
><and "Yesterday's Enterprise" and time travellers in "Captain's Holiday",
><"A Matter of Time" and "Time's Arrow".  It is not clear, therefore, that
><faster than light travel on Star Trek need be such that causality
><violation is avoided.  Let us then try to allow for faster than light
><travel in such a way that preserves special relativity alone and thus
><allowing for causality violation.
>
>You KNEW I would respond to this.

Yeah, but I thought you'd be pleased.

>First,  I do have a problem with many time travel stories in Star Trek.
>No one seems to realize the impact that changing one single thing in
>time can have on future events.  Star Trek always comes out with some
>way of handling it, such as Samual leaving his watch where he knew it
>would be found.  But he HAD to do that, so he didn't have free will.
>But time travel is another discussion all together.

The writers would probably argue this by saying that this is what makes
time travel dangerous, namely that somebody could change the future.
We're supposed to forget how unlikely it is that the present would
remain unaffected by travel to the past.
>
>As far as violating causality through FTL travel, I beleive I have a good
>argument as to why it is not done in ST technology.  If it were, we would
>see its effects all the time!  You get a distress call from a planet. You
>are running out of time to get there.  All you have to do is get in the
>right frame of reference out of warp, then enter warp, and you can get there
>any amount of time after the destress signal was sent or even before it
>was sent.  We do NOT see this at all.  This is why I don't think the idea
>you mentioned about keeping the same F.O.R. you have before you enter warp
>is correct.
>
My way, simply put, is that you observe the same physics in warp
regardless of the speed you were travelling when you entered warp; thus,
there'd be no speed at which you could travel to initiate time travel.

>Finally, you seem to have a problem with me wanting a "special" frame of
>reference as if it violates special relativity all together.           t

(stuff deleted)

I dislike special frames just as you dislike causality violation.

As for what is done on Trek, I see no reason why they couldn't settle
this issue by refering either to a special frame or to causality
violation.  Knowing Oduda and Sternback, they'd probably avoid the
question by coming up with a "Causality Compensator".

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Martin Phipps (aka Cliche Lad)  ! LOULA@hep.physics.mcgill.ca or simply
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Any simularity between myself and a sane individual is pure coincidence.
Newsgroups: rec.arts.startrek.tech