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Path: ...!feeds.phibee-telecom.net!2.eu.feeder.erje.net!feeder.erje.net!proxad.net!feeder1-2.proxad.net!usenet-fr.net!pasdenom.info!from-devjntp Message-ID: <YqTjbAPdSf8P-veYFHQCI8eskLU@jntp> JNTP-Route: news2.nemoweb.net JNTP-DataType: Article Subject: Space-time interval (2) Newsgroups: sci.physics.relativity JNTP-HashClient: ZAfcArzD7Wn6XLGwSo9fnP4Xi0A JNTP-ThreadID: L0IgA2CWtv7gPeDAAk57TJ-BbeQ JNTP-Uri: http://news2.nemoweb.net/?DataID=YqTjbAPdSf8P-veYFHQCI8eskLU@jntp User-Agent: Nemo/0.999a JNTP-OriginServer: news2.nemoweb.net Date: Mon, 12 Aug 24 17:35:41 +0000 Organization: Nemoweb JNTP-Browser: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36 Injection-Info: news2.nemoweb.net; posting-host="e8cbf2474b472b9bb79db3dccb6a856bc1d05409"; logging-data="2024-08-12T17:35:41Z/8984322"; posting-account="4@news2.nemoweb.net"; mail-complaints-to="julien.arlandis@gmail.com" JNTP-ProtocolVersion: 0.21.1 JNTP-Server: PhpNemoServer/0.94.5 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-JNTP-JsonNewsGateway: 0.96 From: Richard Hachel <r.hachel@jesauspu.fr> Bytes: 3061 Lines: 47 The notion of space-time interval should be abandoned because it is complex and leads to nothing, except final errors. What is the space-time interval? A metric, measured in meters. It is mostly an abstract thing that is not very useful. So we set ds²=dl²-c²t². Why and for WHAT? For nothing. For fun. Hachel notation is much more practical, because it does not need the notion of complexes to establish a perfect Pythagoreanism. Hachel does not speak, because he is an immense genius, of the notion of space-time interval, ridiculous and abstract, and he does not use meters, but seconds. That is to say the units of TIME. This is much more practical because from the invariance of ds, which we always wonder what it is, and what it can represent in nature, Hachel goes to the invariance of proper times. It is much simpler and more practical. A proper time is always invariant because it is a tautology, a truism. Hachel then poses Tr²=To²-Et² and speaks in seconds, where physicists stupidly pose -ds²=-To².c²+dl² and speak in meters. Finally, what is ds²? It is just -c².Tr² Let's pose Tr²=-ds².c² and everything becomes much simpler and much more practical. To²=Tr²+Et² Pythagoreanism is perfect. In plain language: In a frame of reference, the square of the observable time is equal to the square of the proper time of the mobile implemented by the square of the anisochrony taken into account. Practical example: A terrestrial observer in a rocket that will travel for 15 years at 0.8c. He will therefore age 15 years. Will the person in the rocket also age 15 years? We set To²=Tr²+Et² Hence Tr²=To²-Et²=15²-12²=81 Tr=9 years. Simplicity is disconcerting. In general, we don't like it too much. R.H.