Past and Future: Travelling in Time
Is time travel possible? Lets see what science has to say
Albert Einstein’s theory of relativity and modern quantum physics put forward the prospect of possible situations for time travel. The theory of relativity says that space and time are interdependent forming the fourth dimension.
It further goes on to say that if one travels at the speed of light (which is 300,000 kilometres per second) relative to other objects, time ceases to exist. As you approach the speed of light, time goes slower for you than the people you have left behind.
For example, you left Earth in 2014 when you were 18 to travel around in space. According to your clock, you have travelled around in space for exactly one year. When you return to Earth, you find that things have changed around you. Technology has advanced and your friends are now married with their children going to school.
By travelling for a year in space, you have travelled 15 years on Earth. Not only did you travel through space but also time. So, you ended up travelling faster in the future.
It also says that the further you move away from the Earth’s gravitational force, time for you slows down. There are situations where one can possibly time travel which have been proven theoretically and also have been featured in a lot of Sci-fi movies such as Interstellar and Mr. Nobody.
Wormhole from the movie, Interstellar
Wormhole: Wormholes are theoretically proven concepts where one can traverse vast amount of space in a very short amount of time. It is like a shortcut to a far-away planet unknown to mankind or the Earth centuries ago.
The cosmologist Stephen Hawking believes that wormholes are all around us. “Down at the smallest of scales, smaller even than molecules, smaller than atoms, we get to a place called the quantum foam. This is where wormholes exist. Tiny tunnels or shortcuts through space and time constantly form, disappear and reform within this quantum world. And they actually link two separate places and two different times.”
The Big Crunch Theory: The Universe came into existence because of a huge explosion called the Big Bang nearly 15 billion years ago. Since then, it has been expanding.
Something called dark energy which comprises 74% of the known Universe is the reason the Universe has accelerated its speed of expansion.
Hypothetically, the Big Crunch is supposed to be the opposite of the Big Bang, where the gravitational forces present are strong enough to counter balance the force of expansion or dark energy.
So, the Universe will stop expanding and contract till the point of its origin, which is to the time of the Big Bang. What will become of time if such an event occurs? Will time move backwards? No one has the answers so far.