The theory of time travel has been a subject that has been discussed among me and my friends while we were amidst large drunken stupors for many years. I think it stems from the fact that many of our favorite movies are based on time travel. Back to the Future, Terminator, Time Cop….all the good ones. But it seems that every movie has contradicted itself. I will use Back To The Future as my basis for this theory and work from there.
The only way time travel can work is seen in a movie I regret to say I watched. Having spent the weekend with the girlfriend, I was forced to watch one of the newer Harry Potters on ABC Family (forced to watch = napping on the couch with her and was too comfortable to complain/I admit I got a little into the plot, but not enough to warrant any reading or viewing). In said Potter film, events are occurring like normal, Harry gets in trouble, but the only way to get out of trouble is to defy the rules, yada yada yada. But while he is trying to escape danger, things are happening outside of their view, helping them escape evil. As the movie goes on, we find that potter and friend go back in time to help themselves. Example: crazy wolf character is about to eat them when they hear another wolf call. Fastfoward to time travel and it is the potter and friend who traveled back in time that made the wolf call. In other words, a type of “destiny” occurred. The future potter and the present potter existed at the same time. No course of history was altered. It happened the way it was supposed to happen, just as after the event was done, potter and friend went back in time to help keep the past the way it should be. If they did NOT go back in time, it would be then that history would have been altered. If they did NOT go back in time, they would probably have been eaten.
This is why if time travel is possible in the future, we would already know about it. Someone would have come back already and we would have discovered that someone in the future will invent time travel because it would already be a part of our history. That is, unless, the person who invents time travel does not travel to a time that has happened already. He may travel to 2020 and then die. Is this a possibility? We’ll just have to wait until 2020 to find out.But say this man from 2020 doesn't die. Say he lives in 2021 and goes back one year for maybe a day to talk to his future self and then goes back to 2021. A year goes by and now that guy has a choice, he has to go back in time to go talk to himself, or he will change history. But it's his choice, he can choose not to and possibly explode the universe or something crazy will happen.
So in one theory I present a type of destiny, where one person going back in time is already set in history because and then there is another that throws destiny way out the window. They both seem extremely right, and that is why I don't really like to think about this much even though I always do when a plot of time travel comes up in the movies.