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From: petrick@lll-crg.ARPA (Jim Petrick)
Newsgroups: net.movies,net.books,net.sf-lovers
Subject: Re: Why shouldn't time travel leave you in the same spot?
Message-ID: <790@lll-crg.ARPA>
Date: Fri, 16-Aug-85 02:59:14 EDT
Article-I.D.: lll-crg.790
Posted: Fri Aug 16 02:59:14 1985
Date-Received: Mon, 19-Aug-85 20:50:01 EDT
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Reply-To: petrick@lll-crg.UUCP (Jim petrick)
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>>Everybody goes on and on about how if you time travel, you should end
>>up way out in space because the Earth is whizzing around the sun.
>
>Nice try Brad -- but wrong. The earth orbits the Sun, the solar system
>[rotates] (etc.)
[a few lines removed from the middle]

What's the problem?  If someone was smart enough to build a time machine in
the first place, couldn't they also think of compensating for these
rotations in some manner?  I know it would be nearly impossible to
determine all the effects of different frames of reference, but then I'd
think that the time travel aspect would be a much tougher nut to crack.
Besides, he could experiment to determine these rotational (etc) effects.

This discussion reminds me of an Isaac Asimov story about two scientists;
one a slow and cautious thinker, the other a quick, jump-to-conclusions
type.  The two are jealous rivals out to outdo each other.  The quick one
invents a device for nullifying gravity, and to show up his rival places
the device on the center of a pool table over a hole cut in the surface.
To embarass his rival, the quick guy invites the slow guy to demonstrate
what a great invention he has by shooting a pool ball across the hole in
the table (and through the null-gravity field).  The slow guy thinks a bit,
then makes a bank shot so the ball is headed directly at the fast guy as it
enters the field.  There is a flash, and the quick guy has a hole punched
through him by the ball (all gravity nullified, it was not accellerated
along with everything else in our frame of reference, and stayed put while
the rest of the world whooshed by).  

	Two questions:  Does anyone remember the title of this story?

			How could the slow guy predict which way the ball 
			accelerated?  

	Jim Petrick
	(petrick@lll-crg.ARPA)