AVENGERS ENDGAME might have confusing storytelling method, but otherwise quite brilliant in explaining time travel concept as they also bring new perspective of it in the name of Quantum Realm, and I would like to discuss several opinions regarding the survived characters throughout the story

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    While no scientific theory has been able to support time travel, infact almost all scientific theories on time travel end up proving that time travel is not possible.. and specially the way we understand it (going into past)

    However, what you will find interesting is that transportation has been successfully experimented.. duplicating existence of a proton at the same time in two different places in space , while maintaining the same weight

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      agree with you @alasecond that no scientific theory able to support time travel (even theories that got honorable mention in the movie).

      But that second paragraph written by yours piqued my interest as I remember Einstein’s relativity theory

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