From: utzoo!decvax!cca!knutsen@SRI-UNIX@sri-unix Newsgroups: net.space Title: Re: Equivalence of Mass and Energy Article-I.D.: sri-unix.2577 Posted: Mon Aug 9 12:54:07 1982 Received: Tue Aug 10 03:41:58 1982 From: Andrew KnutsenActually I seem to recall even the energy of a gravitational field is supposed to exert gravity... this produces some hairy math in gravitational theory.