time travel

[bigtimecow]

alright, i am pretty convinced that time travel (atleast into the past) is impossible, but i would just like to discuss it in a... hypothetical? form.


i have a big question that has been eating at me since i've seen any movies about time travel:

so like, in back to the future when marty goes back to the future (at the end) he watches himself (from afar) in the parking lot and the whole incident with him going back in time. this happens in a lot of movies and i just don't understand how this place in time works out.

so here are two timelines:
1. marty1 goes back in time, does his shit, then goes back to the future and continues living his life
2. (witnessed by marty1) marty2 goes back in time, and i guess does his shit, then goes back to the future and continues living his life.

now, if this were true, wouldn't marty2 go back to the future at the same time, in the same exact place, etc. etc. as marty1? and then marty1 wouldn't witness marty2 going back in time because they would be like, standing right next to eachother.

i might have just answered my own question, further proving that time travel isn't possible. or my thought process is incorrect. i'm not sure.

i know in some movies the time traveler kills his/her double from the past, which i guess kind of works, but i'm not really sure.

your thoughts?