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Path: utzoo!linus!decvax!dartvax!quark
From: quark@dartvax.UUCP
Newsgroups: net.physics
Subject: Re: M = E/C^2 ??? How??? - (nf)
Message-ID: <312@dartvax.UUCP>
Date: Thu, 27-Oct-83 14:17:14 EDT
Article-I.D.: dartvax.312
Posted: Thu Oct 27 14:17:14 1983
Date-Received: Fri, 28-Oct-83 07:54:44 EDT
References: umcp-cs.3375
Lines: 9

Yes, you do get an electron - positron pair from photon decay, but
electron - electron pairs are impossible because, among other things,
charge is not conserved in the interaction. Also, and I'm sorry to
seem so picky, but cosmic rays consist of alpha particles, protons,
etc. in addition to photons.
 
One can get mass from energy in a fusion reaction (you also get
energy), so this isn't all one into the other, but
it is another possibility.