Time travel is always a fascinating idea and a lot of movies adapt it, such as Back to the Future, Terminator, Interstellar, and Doctor Strange. Now it is Avengers: Endgame‘s turn to introduce this concept. The Avengers use the time travel to collect all six Infinity Stones and undo the Thanos’ snap.
Another interesting theory about the use of time travel is about the existence of two versions of Thanos. As we know, there are a younger Thanos and an old Thanos in the two series of Avengers. The younger one is a very ambitious person while the older one is a much more relaxed person. This changing of character is believed caused by the old Thanos traveling back time to let the younger one knows that he will win in the future.
In addition, the visit also let the younger Thanos know that his plan to conquer all humanity will not succeed. He thus changes his plan to only get rid half of the universe.
Besides these two events, the theory also explains the now-famous line that Thanos said to Tony, ” “You’re not the only one cursed with knowledge line.” This saying is argued because Thanos already knew Tony in the previous timeline.
Now it is up to you, whether you believe this travel time concept or not?