Unless changing the past splits time into 2 with both outcomes.
Many-worlds [0]
[0] https://en.wikipedia.org/wiki/Many-worlds_interpretation
Many-worlds [0]
[0] https://en.wikipedia.org/wiki/Many-worlds_interpretation
Really, what is it about quantum physics that causes people to make these weird connections all the time?
(P.S.: The many-worlds interpretation is better called universal wave function theory. Less sexy, but more accurate.)
Time travel, if possible, would be entirely orthogonal.
There is no movement between the "worlds" in "many worlds" (which is part of the reason why "many worlds" is such a misleading label). At best there's interference between them.