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From: gjk@talcott.UUCP (Greg J Kuperberg)
Newsgroups: net.physics
Subject: Re: quo vadis gravity?
Message-ID: <181@talcott.UUCP>
Date: Tue, 11-Dec-84 12:12:54 EST
Article-I.D.: talcott.181
Posted: Tue Dec 11 12:12:54 1984
Date-Received: Fri, 14-Dec-84 04:42:02 EST
References: <184@decwrl.UUCP>
Organization: Harvard
Lines: 20

> 
> >The gravitational field does not "travel" at all.
> 
> If e=mc**2 and matter and mass are converted in an atomic bomb... shouldn't
> something happen to the gravitational field of the "former" mass?

A common myth:  mass is not conserved, energy is not conserved, but the sum
of the two is.  This myth is in part propagated by Isaac Asimov and other
popular science writers.  Now here's reality:  Mass *is* energy, and it is
conserved.  In fact, one more conservation law was thrown in:  momentum.
Whereas B.E. (before Einstein), we had the conservation of mass, the
conservation of energy, and the conservation of momentum, A.E. (after
Einstein), we have the conservation of energy-momentum (energy being equal
to mass).  Energy can be thought of as "momentum in the time direction".
---
			Greg Kuperberg
		     harvard!talcott!gjk

"Strange women lying in ponds distributing swords is no basis for a system
of government."  -Monty Python