In the year 1905 A.D, Einstein published his work that later came to be known as the “theory of special relativity”. The paper consisted of ideas that were far ahead of its time. The theory was revolutionary but also was so unconventional that it shook peoples intuition about space and time. The former concept of time being universal to all the being on and off earth was changed by him. His theory postulates that the speed of light will be same irrespective of the state of motion of its source.
His theory brought about the concept of time dilation. Time dilation simply means, that time runs slower when you travel at speed comparable to the speed of light i.e “c”. Now this may seem to be uncommon or had to visualize but its a proven phenomenon and that is how he discovered the ways for time travel. From his theory the following can be used for future time travel:
It might come as a shock but the people in the international space station that is always rotating earth at a high speed are actually time travelers. Their constant state of motion in comparatively high speed bring about the minuscule level of time dilation. This dilation causes them to age slower than the rest of people on earth. In other words, if we are able to travel at a speed of 90% of light’s speed we will age 2.6 times slower than people on earth. Travel now at that speed and leave earth, if we come back after 4 years the earth will have already advanced by 10 years. That means we literally jumped 6 years of earth time. Though our friends on the ISS don’t experience such big time jump, but they do gain some very very small amount of extra time.
The particles that runs through particle accelerators like LHC, are very lucky. They travel at a speed of 99.99% of speed of light and for them 1 sec is equal to 11 months on earth normal time. This is the result of time dilation and thus Einstein discovered or more like theorized it.
The other method also came from Einstein. This time general relativity. In general relativity he introduced the concept of how the universe experiences the space and time as wide spread cloth that can bend when an object is placed over it. For simplicity imagine a stretch trampoline with a heavy ball in the middle. Those curves around the ball is the bend in space and time. Now if the ball is big enough to bring about a major bend in space and time, he says it can slower the time. Precise atomic clocks at different gravity level have been used to test for this phenomenon and turns out, it is true. When an object is subjected to heavy gravitational force it experiences a slower time. Practically, we would need a very heavy object like a black hole or other such scale heavenly bodies to see a significant time jump for us. Though it seems not feasible for humans any time soon, the clocks on the satellites seem to experience it all the time. Those clocks and the clocks on earth are required to be constantly synchronised taking in account for the gravity to keep them functioning.
The GPS satellites are constructed taking in account for both the time dilation and gravitational effects. If any one of them is left out, your GPS won’t be working as precisely as it should be.
As explained in the movie “Interstellar”, wormholes are holes in spacetime connecting two different points of space and time. These “holes” in spacetime are also the solution to the equation published by Einstein in his theory of general relativity. Theoretically, anything that goes through wormholes can jump between two points of space and time. It is believed that many wormholes are being constantly created and destroyed in the quantum level but finding a wormhole that can fit a person or a spaceship is a challenge yet to be completed.
Apparently, time travel isn’t really an unattained dream at this point. The only compromise is it is not significantly large and we can’t seems to control at which point we exactly want to go. If you are still thinking about traveling back in time then it is discussed in this post. What you think about time travel? let us know in the comment.