Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site jhunix.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!genrad!panda!talcott!harvard!seismo!umcp-cs!aplcen!jhunix!ins_apmj From: ins_apmj@jhunix.UUCP (Patrick M Juola) Newsgroups: net.physics,net.research Subject: Re: Newman's Machine (brief) Message-ID: <1077@jhunix.UUCP> Date: Thu, 31-Oct-85 10:22:21 EST Article-I.D.: jhunix.1077 Posted: Thu Oct 31 10:22:21 1985 Date-Received: Sat, 2-Nov-85 07:47:18 EST Reply-To: ins_apmj@jhunix.ARPA (Patrick M Juola) Distribution: na Organization: Johns Hopkins Univ. Computing Ctr. Lines: 18 Keywords: Relativity, paradox Xref: watmath net.physics:3465 net.research:311 Summary: A dumb physics question This ought to take some physics major about ten seconds to bat out a reply, but I'm a math major and really confused about this problem -- To wit : It's fairly common knowlege that if I were to get into a space ship and go away at close to the speed of light then come back, I would age less than my girlfriend whom I left back on Earth. Anyone who's watched Cosmos knows that much. However, why am I the one who ages? If motion is relative and my ship is an inertial reference frame, why can't I assume that the earth is going away from me at close to the speed of light, and that my girlfriend would therefore be aging more slowly than I would? Send replies by E-mail; no need to clutter up the net with ten thousand copies of the same flaw in my reasoning. Thanks in advance. Pat Juola Johns Hopkins Univ. Dept. of Maths