Well that's just it, my understanding is that FTL hasn't been proven to violate causality, or that causality is inviolable. It's just very strongly hinted at.

	▲	jdranczewski 2 days ago \| parent [-]
		In special relativity at least it's pretty clearly the case that communication outside the light cone (so faster than light) will result in events happening in the wrong order in some frames, violating causality. I will not speak of general relativity, as while I've taken a course in it, years later I have returned to considering it largely dark magic.

▲

bee_rider 2 days ago | parent | prev [-]

Supposing you transmit a message to me at a prearranged time, a number. At that prearranged time I pick a number at random, and act as if it is your message.

When I eventually get your message some time later, if it turns out my random pick was wrong, I kill myself. If the many worlds interpretation is right, I should only observe universes in which I’be managed to conjure up your message faster than causality, right?

▲

Ukv 2 days ago | parent | next [-]

> If the many worlds interpretation is right, I should only observe universes in which I’be managed to conjure up your message faster than causality, right?

I feel that's pairing MWI with some non-physical (or at least beyond the wave function) overarching "I" that can see across or jump between branches of the wave function, whereas I'd claim the appeal of embracing MWI is largely that the universe's wave function is all there is and observers/consciousness play no special role (along with not having nonlocal random "collapses"). The experiment would be no different than gathering a bunch of people, assigning each a number, then killing the ones that were assigned the wrong number once the real number arrives.

▲

bee_rider 2 days ago | parent [-]

It isn’t any jumping, just from an individual’s point of view they can’t have been somebody who ended up dying.

	▲	Ukv 15 hours ago \| parent [-]
		An individual can end up dying - they'd experience themself seeing the wrong number, then committing suicide. There wouldn't be anything after that where an individual can "observe universes" with the ones where the wrong number was predicted taken out of the possibility pool - that individual is just dead.

▲

jdranczewski 2 days ago | parent | prev [-]

Long term, sure. Short term I think an unpleasant number of your parallel universe copies would observe themselves dying.