Path: ...!weretis.net!feeder8.news.weretis.net!pasdenom.info!from-devjntp Message-ID: <4P8P35rGVs_krWmhPcI_Wdi0QP0@jntp> JNTP-Route: nemoweb.net JNTP-DataType: Article Subject: Re: What is "local =?UTF-8?Q?time=22=3F?= References: Newsgroups: sci.physics.relativity JNTP-HashClient: 1WAEEwyMn2jY2_ngyKZgOkUJx2g JNTP-ThreadID: -D6LOzWQs9eNxLCiLkhFDtCIJBk JNTP-Uri: https://www.nemoweb.net/?DataID=4P8P35rGVs_krWmhPcI_Wdi0QP0@jntp User-Agent: Nemo/1.0 JNTP-OriginServer: nemoweb.net Date: Wed, 16 Oct 24 13:07:58 +0000 Organization: Nemoweb JNTP-Browser: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36 Injection-Info: nemoweb.net; posting-host="e8cbf2474b472b9bb79db3dccb6a856bc1d05409"; logging-data="2024-10-16T13:07:58Z/9062999"; posting-account="4@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 Bytes: 2834 Lines: 33 Le 16/10/2024 à 11:03, Mikko a écrit : > On 2024-10-14 11:28:45 +0000, Richard Hachel said: > >> What is "local time" in relativity? > > The expression is usually not used in Relativity. In particular, > Einstein did not use it. You may be right. For my part, I firmly believe that a lot of words or concepts should be completely abandoned. This will make many relativity lovers jump, I think, but I think it is "necessary for the song" and that one day, we will have to go through it. Example of words or concepts that are TOTALLY useless, even biased. "local time", "relativity of simultaneity by change of reference frame", "local present time", "hypercone of present time", "invariance of the space-time interval", "time-gap": we don't need all of this. At best, it is useless, at worst it is false. And this is only part of the horror that misunderstood RR has become, and I am not even talking about uniformly accelerated media and rotating media. The RR that should remain compatible is so much no longer compatible that we are forced to talk about RG to sweep the dust under the carpet. The same goes for a simple Langevin in apparent speed, it is so ridiculous that we are forced to evade this question, and that no one except me is capable of drawing a simple little space-time diagram for the two protagonists where the lines of simultaneity are horizontal in the present time hyperplane of each. All this is absurd. How many more years or decades before all these stupid notions jump out of the textbooks? R.H.