Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Paul.B.Andersen" Newsgroups: sci.physics.relativity Subject: Re: Langevin's paradox again Date: Wed, 10 Jul 2024 21:01:44 +0200 Organization: A noiseless patient Spider Lines: 65 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Wed, 10 Jul 2024 20:56:46 +0200 (CEST) Injection-Info: dont-email.me; posting-host="766ee97878832b8934cea0bc86f786a7"; logging-data="2132199"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/hcSQtPua9JplHjmFMcdhT" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:V+F+MLo2i8E8Zey8Pkp8hoR7ntg= Content-Language: en-GB In-Reply-To: Bytes: 3522 Den 09.07.2024 15:47, skrev Richard Hachel: >> Am Sonntag000007, 07.07.2024 um 23:05 schrieb Paul B. Andersen: >>> Den 04.07.2024 15:30, skrev Richard Hachel: >>>> Langevin's paradox. >>>> The Langevin paradox is a very serious criticism against the theory >>>> of relativity. >>> >>> Langvin's paradox is another name of the "twin paradox". >>> In 1911 Langevin gave an example of said "paradox". >>> He showed that the twins' would age differently. >>> This was nothing new, Einstein gave an example of it >>> in his 1905 paper, but he only mentioned the phenomenon >>> without numbers. But Langevin gave an example where >>> the "travelling twin" was moving at the speed 0.99995c >>> (γ = 100) which made the "travelling twin" age 2 years >>> while the "home twin" aged 200 years. >>> Neither Einstein nor Langevin thought that this falsified SR. > > The paradox is this: The greatest relativistic physicist in the universe > (Richard Hachel) said that the effects of physics are reciprocal by > permutation of observer, and therefore, if we take the INTERNAL > mechanism of two watches, each will beat faster than the other, both on > the outward and return journey, or during a long circular journey. > A very naive notion. 😂 Let's look at the following scenario: - Twin A and twin B are inertial and co-located. - Twin B accelerates at the proper acceleration 2 c/year away from A for 1 light year [ly] in A's rest frame. - Twin B coasts (no engine) for 8 light years until he is 9 ly from A. - Twin B accelerates at 2 c/year towards A. He will reach 10 ly and go back to 9 ly when he stops the engine. - Twin B coasts from 9 ly to 1 ly- - Twin B accelerates at 2 c/y until he is co-located with A. The scenario can be simulated here: https://paulba.no/twins.html Here are screenshots of the simulation: https://paulba.no/temp/Twins_run.pdf Note: While B is coasting and inertial we have two inertial twins moving at the constant speed 0.943 c relative to each other, and both will measure the other twin's clock to run slow by the factor 0.333. Yet B ages 9.18 years while A ages 22.63 y. B's accelerations make all the difference. The greatest relativistic physicist in the universe (Richard Hachel) will probably not read this, and if he does i won't understand it. But there may be lurkers? -- Paul https://paulba.no/