Time travel movies are a favorite of mine. I love how they show situations that seem impossible or contradictory. One example of a paradox is the “Grandfather Paradox”, where you can go back in history and kill your grandfather. This would stop your own birth. If you were not born, you wouldn’t be able to kill your grandfather. Thus, a paradox. The problem is that time travel is not real and we have no way to know what it looks like. A number of time travel movies have shown multiple ways time travel can work. Because I have always been fascinated by the idea, I thought it would make a great topic to discuss the various types of time travel. This Is Barry’s time travel list
A Unchangeable Future
This type of time travel allows you to see the past, present and future in a way that is unalterable. This idea may have been explored in Terminator. If the Terminators could go back in time to kill John Connor, that wouldn’t matter because someone else would have taken Connors place in the army, and performed the same acts as he did in future. In Terminator 2: Judgement Day John, Sarah and the T-800 explode Cyberdyne to supposedly stop Judgement Day. Terminator 3: Rise of the Machines shows Judgement Day. Skynet could still find a way for Judgment Day to occur, even if John or Catherine had been able stop Judgment Day from T3. According to the T-850, “Judgement Day” is inevitable. This time travel type ensures that the future, regardless of how the past or present changes will be the same. You can go back in time to kill Trump. In 2017, another angry orange billionaire will be elected president. If the future, present, or past are inexorable, then paradoxes are impossible. This principle is called the Novikov self consistency principle. It has some flaws, but it’s still a fascinating concept. This principle was also used in Harry Potter’s time travel and the Prisoner of Azkaban.
Time Reversal
This type of time travel is less common and has been featured in movies and TV shows. This type of time travel allows you to go back in time and you get younger each time you go back. If I could time travel back to 2017, my arrival in 2017 would be five years earlier than me now. However, I will still have all of my current knowledge. These types of time travel raise some questions. Would you be able to travel back in time to the year before you were born? Or would you slowly age backwards to find yourself a fetus again? If you could travel back in time to the year 3000, wouldn’t you see yourself growing old and dying in the time machine. This is because you age according to how much time you travel. Men In Black 3’s time jump used the “Multiple Timelinesî type of time travel. However, in the above scene, it uses “Time Reversal”. Boris shoots at J and then he recalls the shot pattern and tackles Boris. The two of them are sent back to the time they were in a few seconds before. The two of them have aged backwards, and instead of having TWO Js or TWO Borises on this structure, Boris can’t travel back in time, but J does.
Changeable Past, Changeable Future
This type of time travel allows for the Grandfather Paradox. If you can travel back in time, you can change the past. This can dramatically change the future. Marty, who accidentally prevented his parents from falling in love and meeting, had to bring them together again. If he didnít, Marty wouldnít have children, Marty wouldnít have been born, and Marty wouldnít have been able to travel back in time. We start to see Marty slowly fade away from existence. Had his parents not gotten together, the paradox would have been complete and Marty would have been extinct. This kind of time travel allows you to change the past and create a completely new future.
Multiple Timelines
This type of time travel allows you to change the past and future at will. But paradoxes are impossible. Consider Marty’s actions in the original Back to the Future. Marty’s parents would have never been reunited had he used this kind of time travel in the movie. He would have created a new timeline where Marty McFly wouldn’t exist. This idea was later used in Back to the Future Part II. Old Biff uses his DeLorean to travel back to 1955 to give his younger self a sports almanac. By 1985 Doc is committed to a mental hospital and Marty is at a school in Switzerland. Doc wouldn’t be able to create the time machine that allows Biff back to 1955 if he was in a mental facility in 1985. If the laws of time travel were the same as the first Back To The Future then a paradox would have occurred.
