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From: guido wugi <wugi@brol.invalid>
Newsgroups: sci.physics.relativity
Subject: Re: New Terrell Rotation Animation
Date: Sun, 9 Feb 2025 18:54:22 +0100
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Op 9/02/2025 om 16:25 schreef ProkaryoticCaspaseHomolog:
> This morning, I completed an animation for Wikipedia
> https://commons.wikimedia.org/wiki/File:Terrell_Rotation_and_Illusory_FTL.gif#%7B%7Bint%3Afiledesc%7D%7D 
>
>
> No major insights, but it was fun to program. I've added it to the
> article on Special relativity
> https://en.wikipedia.org/wiki/Special_relativity#Measurement_versus_visual_appearance 
>

Nice work! I've seen earlier well-done German animations, don't know 
where I kept the links though.
About "Measurement_versus_visual_appearance", that has always been a 
topic of interest to me, and it took years (if not decades:) to see it 
trickle in to SRT descriptions (before that, there was general confusion 
between both descriptions, still going on in some minds:).

Here are my latest Desmos exercises on it:
https://www.wugi.be/srtinterac.html (under: Measuring relativistic 
motion, and Seeing it)
(older QB examples at https://www.wugi.be/paratwin.htm and 
https://www.wugi.be/qbRelaty.html)
"Terrell rotation" can be seen at work in all kinds of position, in 2D. 
The only "direct vision" of pure Lorentz length contraction is far away 
along the observer-based perpendicular [line/plane] to the direction of 
motion.
:(I'm confident though that my graphs won't make it to Wiki):

-- 
guido wugi