Path: csiph.com!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail From: Mike Fontenot Newsgroups: sci.physics.relativity Subject: Re: Idiocy Called Twin Paradox Date: Mon, 11 Apr 2016 17:35:56 -0600 Organization: A noiseless patient Spider Lines: 31 Message-ID: <570C34DC.3020109@comcast.net> References: <4fedfaf0-391f-41e4-b84b-fcd5ce2dd839@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Injection-Info: mx02.eternal-september.org; posting-host="ba1e2a899132d15169c30f820eb6257c"; logging-data="25467"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX189jT6BpqA/8JHdlxIN1q+2" User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 In-Reply-To: Cancel-Lock: sha1:MTvzy9sfrOh81dV3tCOAgt+enPI= Xref: csiph.com sci.physics.relativity:381404 On 4/11/16 3:45 PM, rotchm wrote: > On Sunday, April 10, 2016 at 2:59:09 PM UTC-4, Pentcho Valev wrote: > >> The traveling twin turns around, and this act of his miraculously >> makes the distant stationary twin on the Earth older. > The acceleration by the traveler causes the traveler's conclusions about the home twin's current age to rapidly change (relative to the traveler's own rate of ageing). If the traveler is accelerating TOWARD the home twin, he will conclude that she is rapidly getting older (assuming their separation is sufficiently great). If he is accelerating AWAY FROM her, he will conclude that she is rapidly getting younger (again assuming their separation is sufficiently great). But in neither case does the home twin conclude that anything unusual is happening to her rate of ageing. Nor do any other inertial observers conclude that her rate of ageing is changing because of the traveler's acceleration. It strictly has to do with the TRAVELER'S PERSPECTIVE of her rate of ageing. And it is the rapid ageing of the home twin (according to the traveler) during the turnaround that results in the agreement of the two twins about their respective ages when they are reunited, given that the traveler says she aged more slowly than he did on the steady-speed portions of the trip. -- https://sites.google.com/site/cadoequation/cado-reference-frame "Accelerated Observers in Special Relativity", PHYSICS ESSAYS, December 1999, p629. All you ever need to know about the twin "paradox".