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From: "Paul.B.Andersen" <relativity@paulba.no>
Newsgroups: sci.physics.relativity
Subject: Re: Langevin's paradox again
Date: Wed, 10 Jul 2024 21:01:44 +0200
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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/