Is time travel possible? Scientists say it is ‘theoretically feasible’
A lot of people would love to time travel – to go back in history and see the dinosaurs or meet famous people, or to jump into the future to see what life is like. Unfortunately, as far as we know, time travel is not possible.
The laws of physics seem to preclude it. For example, Einstein’s theory of special relativity says that time slows down for a moving object. So, if you were to travel near the speed of light, time would slow down for you. But even if you could travel at the speed of light (which is impossible, according to Einstein’s theory of general relativity), you still couldn’t travel back in time.
The reason is that, according to general relativity, time is a fourth dimension. It is not something that you can move along, like the other three dimensions of space. Instead, it is something that exists independently of space and time.
So, if time travel is not possible, why do scientists say it is “theoretically feasible”?
The answer has to do with a branch of physics called quantum mechanics. Quantum mechanics is the branch of physics that studies the behavior of subatomic particles. Subatomic particles are particles that are smaller than atoms.
Quantum mechanics says that subatomic particles can exist in more than one state at the same time. This is called superposition. So, a particle could be in two places at the same time, or it could be in two different energy states at the same time.
This might sound like nonsense, but there is experimental evidence that supports the theory of superposition. For example, physicists have observed subatomic particles in two different places at the same time.
This weird behavior of subatomic particles leads to some interesting consequences. One of these is the possibility of time travel.
Theoretical physicist Stephen Hawking has proposed a method of time travel that is based on the principles of quantum mechanics. Hawking’s method of time travel is called “quantum tunneling.”
Quantum tunneling is a process whereby a particle can tunnel through a barrier that it cannot surmount. The particle does not have enough energy to surmount the barrier, but it can tunnel through it.
Think of it like this: imagine you are trying to get to the other side of a wall. You don’t have enough energy to jump over the wall, but you might be able to tunnel through it.
Hawking’s proposal for time travel is based on the idea of quantum tunneling through time. The basic idea is that, if you had a particle that was in two places at the same time, it could tunnel through time.
So, if you could find a way to put a particle in two places at the same time, you could use quantum tunneling to travel back in time.
Hawking’s proposal is just a thought experiment. He has not proposed any way to actually put a particle in two places at the same time. But, if it were possible, it would be a way to travel back in time.
There are other ways to travel back in time, but they all have serious problems. For example, one way to travel back in time is to go faster than the speed of light. This is called “time dilation.”
Time dilation is a real phenomenon. It is predicted by Einstein’s theory of special relativity. And, it has been observed in experiments.
However, time dilation does not allow you to travel back in time. It only allows you to travel forward in time. So, if you were to travel at the speed of light, you could travel forward in time, but you could not travel back in time.
Another way to travel back in time is to go around a black hole. This is called the “time machine” method.
The idea is that, if you could find a black hole, you could orbit it. As you orbited the black hole, you would travel forward in time. But, as you got closer to the black hole, you would travel back in time.
So, if you could orbit a black hole, you could travel back in time.
However, there are two problems with this method. First, it is not clear that black holes even exist. Second, even if black holes do exist, it is not clear that you could orbit one without being pulled into it.
So, as far as we know, the only way to travel back in time is to use quantum tunneling. But, as of yet, there is no way to actually put a particle in two places at the same time. So, for now, time travel is still just a theory.