And who does not like to travel? Obviously, it’s interesting to explore different parts of the world. We can travel different places. What if we can travel “in different times” too (we indeed travel in time, but only in one direction, to the future)! Sounds fascinating, ah? Let’s continue then about time & time travel…
Nature of Time?
Newtonian Physics assumed time to be an absolute quantity. But later on Albert Einstein introduced “The Special Theory of Relativity” (STR). I will not go to those equations of STR here. But, the core point is that time is not an absolute quantity as thought earlier. Time indeed depends on the motion of the observer(s). In fact time is not universal i.e. the clocks of two observers may not “tick” the same way all across the universe; one might tick slower or faster than the other.
Consider a girl inside a moving train and a boy at rest on the ground (with respect to Earth). So, time slows down with respect to that girl than the time with respect to the boy. The boy will observe things happening at a slower rate inside the train while the girl will see things happenings faster around the boy.
In fact time is not universal i.e. the clocks of two observers may not “tick” the same way all across the universe; one might tick slower or faster than the other.
A thought might have come to your mind that why it is not obvious to us then. This is because our day to day motions are confined to speeds which are very very less comparable to the speed of light (299,792,458 meters per second!!). The more the speed of an observer approaches the speed of light; time slows down than an observer at rest. Technically this is called time dilation. At the speed of light, time eventually stops, wow!! Time travel can happen, below is how.
Through the wormholes:
The theory of general relativity also predicts some objects like Wormholes. Wormholes can be considered as space-time shortcuts. It’s like you enter to the wormhole from one side and in the other side you reach at a new space and time (in past or future). Wormholes could have been good means to travel back to the past, but to create a wormhole which is larger enough to transport humans is practically impossible now. A wormhole eventually destroys itself due to feedback-effect! Don’t be sad, our future technologies might produce wormholes which are stable enough and we might have a tour.
Using black holes:
Black holes are stars which are so massive that not even light can escape them, they appear black! Well, things will change a bit here that can strike your common daily senses, the mass of the black holes adversely affects the way space and time behaves. Around a black hole time runs very very slow. So, if an astronaut manages to travel in his space ship around a black hole for minutes then come back to Earth, he can see the future!!
So, remember, the faster you move, the slower is the time with respect to you than an observer at rest!! If you like this article, comment your views and questions below.