Comments by "EebstertheGreat" (@EebstertheGreat) on "Why Going Faster-Than-Light Leads to Time Paradoxes" video.

This is categorically false, as some people have already pointed out, and it's really frustrating that you don't edit your post (or simply delete it) and prefer to continue to misinform people. The inability to communicate using quantum entanglement is one of the classic "no-go" theorems of quantum mechanics called the No-communication theorem. Although it might appear intuitive that you could send a message in this way, you will always fail. If Alice and Bob have an entangled pair of particles, in any state whatsoever, there is nothing Alice can do to her particle that will be observable by Bob unless she sends additional classical information. That's just a fact. And if you could send a message back in time, that would absolutely violate causality, in exactly the way explained in this video. Sending information back in time to alter the original message is clearly paradoxical.
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@yourbestfreind777 This is very definitely not being discussed at the highest or any other level. The relevant theorem proving the impossibility in general is due to Ghirardi, Rimini, and Weber in 1980.* Following this paper, some more results were published in the 1980s that effectively ended the discussion. The assumptions required to prove this result are very weak and very general. And it's hardly surprising, frankly, since superluminal communication is patently paradoxical. [*] "A general argument against superluminal transmission through the quantum mechanical measurement process." G. C. Ghirardi, A. Rimini, and T. Weber. Lettere al Nuovo Cimento vol. 27 no. 10. 8 March 1980. https://sci-hub.st/10.1007/bf02817189.
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@uncleanunicorn4571 Although it is a bit involved, you can see that if you can travel superluminally at all, it is always possible to travel back in time in three steps, two of which is superluminal and one of which is subluminal. You can always reach the same place you were at at the start, in the same reference frame, but at an earlier time. PBS Spacetime had a decent video describing this: youtu.be/HUMGc8hEkpc.
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