Of course this is only my uneducated opinion. I belive that if one were to travel back in time, they could make no changes, because the only way for him to come back to attempt to change the past is the exact time line he took before he went back in time. So if he were in the past all actions he made must have been made before he traveled back in time for the varibals to be parallel. So no real change can be made. If he were to deviate from the path he previously traveld to go back in time, to change the result in any way where he would not end up going back. It would be like he never did because then he would have never gone back to make that choice to not go back in time. Thats just my idea. Correct me if im wrong please
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