There’s a time travel detail in Endgame that still bothers me.
Present day Nebula travels back to 2014 and eventually kills her younger self, So why doesn’t present Nebula disappear?
Because Endgame establishes that traveling into the past doesn’t rewrite your own history, It creates a branch.
So when 2023 Nebula kills 2014 Nebula, she isn’t changing the past that created her. She’s creating a new timeline where that version of Nebula dies….The original Nebula survives because her own history remains untouched.
But here’s where the paradox gets interesting.
If killing your younger self doesn’t erase you, what happens if you prevent your own birth?
Would you continue existing because you came from another timeline, or would that branch simply exist without you?