For Nima Arkani-Hamed, the constant speed of light should be introduced because "we don't want arbitrarily distant regions in the Universe to be able to affect us":
https://m.youtube.com/watch?v=KPerMYif2oE
RELATIVITY - Galileo to Einstein - Nima Arkani-Hamed
The same Nima Arkani-Hamed teaches that spacetime, the consequence of the constant speed of light, does not exist (true premise, nonexistent consequence!?!):
https://www.youtube.com/watch?v=U47kyV4TMnE
Nima Arkani-Hamed (06:09): "Almost all of us believe that space-time doesn't really exist, space-time is doomed and has to be replaced by some more primitive building blocks."
We all live in Einstein's schizophrenic world, don't we?
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