Time travel has probably been one of man’s wildest fantasies for centuries. Today, the concept of time travel has become a staple of science fiction books and movies, wherein the protagonist embarks upon a journey either forward or backward in time to save the world from the ultimate evil, or for the greater good, or maybe just to fix a past mistake. Be it ‘Star Trek’ or ‘Action Replay’, time travel has made its way into most of the latest hits of the twenty first century. Though, present scientific equipment or machinery are not advanced with required technology to make this a reality, the theoretical concept of time travel has been discovered and to some extent, even established by physics.
This concept was first unveiled by Albert Einstein’s theory of relativity. It is first however important to understand that two objects having mass exhibit a force of attraction on each other known as ‘gravity’ at all times. This tug of force differs with the mass and distance between the two bodies; meaning that even though the center of the earth is pulling you towards it, keeping you firmly rooted to the ground, your center of mass is pulling back at the earth. But the more massive body hardly experiences the tug from you, while you remain upright, thanks to the same force. Einstein, in his theory determined the laws of physics are same for all stationary objects and he showed that the speed of light in a vacuum remains same no matter what the speed of an object maybe. This brought him up to draw a conclusion that space and time were woven into a single fabric known as ‘space-time’, which bends in accordance with the mass and nature of object, in a way similar to that when a trampoline dimples when you jump on it.
The entrance to a wormhole.
Perhaps the easiest way to understand this concept is to examine a simple hypothetical model of a time machine known as a ‘wormhole’. A wormhole could be imagined as a long tunnel, with two ends each at different points of time or location. It could connect extremely long distances such as a billion light years or even a few meters, different universes or even different time zones to allow a person to travel backward or forward in time, through it.
However, one of the major contradictions of the theory of time travel is the ‘Grandfather Paradox’. Consider yourself in a situation in which you have been able to achieve the level of technology to create a time machine and practically move through time zones, be it the past or future. In such a case, you decide to travel back in time, to the era of your ancestors, say your great grandfather, and plan to kill him. However if you are successful in doing so, it would mean that your family tree ends there, your grandparents, parents, and ultimately you, yourself would cease to exist. How can you then explain your presence or even your existence in that very moment?
While the possibility of time travel seems to tantalize physicists and laymen alike, the odds seem to be against it. In fact, according to current discoveries, the amount of energy required to travel through time would be greater than the sum total of energy present at earth, thus making it practically impossible. However, as much as the idea of time travel seems to counter our common sense and understanding of reality, the universe is the way it is, whether we like it or not. Even if this notion of moving through time seems difficult presently, we must not forget that the history of physics, has, time and again forced us to change our cherished notions of reality. So, time travel, a possibility in the near future or not? I leave the question up to you.
Do you think time travel can be real? Share your thoughts in agreement with or against the author’s points or start a discussion in the comments down below! If you liked what you read, press the like and share.