Back to the Future. Terminator. The Philadelphia Experiment. The Final Countdown. The Time Machine, of course. All of these fantastic tales are centered around the possibility of moving through time, both forward and backward. Now there are many other tales, published and unpublished that involve time travel. And why not? It is one of the most intriguing concepts man has ever come up with. Time travel. But is it a possibility?
First, let’s discuss the possible paradoxes. The first is my favorite – the Grandfather Paradox. It was first posited in the 1943 Rene Barjavel novel Le Voyageur Imprudent (Future Times Three). In essence, it says that one cannot travel back in time to kill their own grandfather before he has children. Because if you kill your grandfather before he has children, then he did not give life to his son- your father- and then you. So if you were never born, how could you have gone back in time to kill your grandfather? There is also the philosophical concept of autoinfanticide- killing the baby version of you. Again, if you kill yourself as a baby you can’t ever grow up to become the adult that travels back in time to kill the baby you.
The next paradox is the Temporal Causality Loop. A great example of this is the Black Sabbath song Iron Man. In the story of the song the protagonist travels back in time via a magnetic field –which turns him into the mute Iron Man- to warn humanity of impending doom. But because he was unable to communicate, he was ignored and mocked. This led him to become enraged and destroy the world as we know it- causing the very cataclysm he traveled through time to prevent.
Another problem with time travel is that while you might be going back to do something noble – killing Hitler or preventing Martin Luther King’s assassination – could have far reaching ramifications, the consequences of such are incomprehensible. It’s basically the Butterfly Effect – if a butterfly flaps its wings in San Diego it causes a tidal wave in Tokyo. In essence it says that even the smallest actions could affect life in ways that could be cataclysmic. You cannot possibly imagine what your actions could lead to; by changing the past you are setting into motion an alternate reality that may in fact be far worse than the reality before you changed things.
As far as time travel as a scientific possibility – it has already happened. When an astronaut goes into space and travels as fast as spacecraft actually travel when he or she comes back, they are actually a fraction of a second younger than they would have had they stayed on Earth. Not very impressive, I understand. But based on Einstein’s Theory of Relativity, time slows as speed increases. So if you could travel at the speed of light in a spacecraft, you would age slower than you would on Earth.
Another way of manipulating time and executing time travel would be with the creation of a worm hole. A worm hole is like a shortcut in space. It’s like a tunnel through a mountain; instead of traveling around the base of the mountain you can travel directly through it drastically reducing travel time. Imagine two points on a piece of paper. Now fold the paper so that the two points are touching. This is the concept of a worm hole as demonstrated by theoretical physicist Michio Kaku.
Is time travel possible? In Carl Sagan’s book Cosmos he describes a craft called Orion which would be capable, at the time of the writing in 1980, of attaining a speed of 18,600 miles per second, or one tenth the speed of light. If there was a way to make this a reality and also a manned craft this would provide a way to cheat time. Because of the vast distances in space from planet to planet and the incomprehensible distance (and time it would take to travel) the only way to get from one place to another in the galaxy is to travel at speeds that would retard the aging process. Scientists theorize that traveling through black holes is one way of circumventing space and time. Of course, there is no way of knowing where or when you will come out on the other side of the black hole or a worm hole, should we find one or develop a way of artificially creating one. Then of course, we would need to then construct a craft capable of traveling through the crushing gravitational forces of a black hole. Is time travel something that is achievable in our lifetime? Is time travel something that could even be accomplished at all or is it just science fiction? You decide. Courtesy of Patrick Rahall, contributing author