Man arrested at large hadron collider

[Evan_]

If the time travel occured for the sole reason to prevent something that have happened prior to the time travel, then preventing it would erase the reason of the time travel.

That's not too hard to solve. You just need to stick a note somewhere where your future self will find it, explaining him that he needs to time-travel to do this and that to prevent the birth of an endless cycle of parallel universes playing pong with his(your) self.

Maybe sticking a photo of yourself doing something memorable and stupid would also help convincing yourself that it's just the future you and not some idiot prank.

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