Man's desires are infinite. Due to the advancement of science and technology, today's man intends to do everything that a man could not have imagined a hundred years ago. But even today, in spite of the tremendous progress of science, man is helpless in many things and many questions remain unanswered such as the mystery of time travel, which means to go into the past or the future from one's present. "No man can jump twice into the same river" or in Urdu, "gone days never return back", we have heard many such proverbs. In this video, we will learn about what time travel is and whether time travel is possible or not What does science know about this so far? Is there anyone who claims to be a time traveler?
What is Time Travel?
What is time travel? The shortest definition is “to travel in time”. That is ; going from your present into the past or the future To take a simple example, we are all moving forward in time Every year on our birthday, our age increases by one year as we travel in time. But friends, we all have the same speed of this travel. That is, we all spend one second per second. Is it possible for us to go back or forward from the present? Different scientists have put forward different theories about this. According to some, this is possible, while others reject the idea.
Einstein's Theory
We have all read somewhere about Einstein's theory of relativity. According to this theory, time is not a constant but a relative and it depends on each person's own observation - suppose you are traveling in a train. Now, according to you, all the passengers inside the train are still and their time is passing slowly while for a person on the road outside, all the passengers of the train are moving and their time is also passing fast. The theory of relativity explains the same difference of observation. The speed of light is the highest and nothing can travel faster than it. Suppose a person is traveling at the speed of light in a spaceship - According to the theory of relativity, in a few years, he will be younger than his twin brother on Earth because of the traveling with the speed of light as his time is passing slowly. This is called time dilation. According to Einstein, time is the fourth dimension, while the other three dimensions include length, width, and height.
These three dimensions tell us the location while the fourth dimension tells us the direction and it only goes forward in time and passed time never gets back. When something is placed on this four-dimensional frame, it bends from this place. This bending represents gravity. The second important concept is related to the same gravity - that the farther a spaceship or an object from gravitational force, the faster time will pass.
But the difference is very small. And speed has more effect on time than gravity has. So there is very little difference between the age of an astronaut and that of a normal human being and these astronauts are a few milliseconds younger than ordinary people.
Warm holes are a great way to travel in time. A warm hole is connected to another warm hole through a tunnel. These two exist at two different times or eras. That is, if you enter one warm hole and exit the other, you may reach a hundred years back from today. But these are just theories because these warm holes are very difficult to detect and it cannot be said with certainty whether they actually exist or not. And even if they do, they are very small and it is said that if something goes inside them, they will disappear. Another way to travel in time was given by astronomer Frank Tipler. According to this, if a substance that weighs ten times more than the Sun is wrapped and turned into a long cylinder and rotated several billion times in a minute then the spaceship near this cylinder will be able to travel in time. This method is also not very effective. And it's very difficult to turn that into reality.
Another way is to rotating of a spaceship around a black hole. Gravity in black holes is so intense that nothing, not even light, can escape it. Its concept is that if a spaceship rotates around a black hole for five years, then five years later, ten years would have passed on Earth and only five years would have passed in the spaceship. That is, all the people who were in the spaceship will be five years younger than the people on Earth.
One of the most popular ways to travel in time is the time machine. This concept has been shown in many films. The concept of a time machine is that it wraps space-time frame (three dimensions of space and one dimension of time) in the form of the loop around itself in such a way that its starting and ending point comes in one place. To turn this concept into reality requires a substance whose properties are quite different from those of ordinary matter. This substance is theoretically present, but in fact, nothing can be said definitively about whether such a substance exists
However, even if such a substance is found, it is said that it will be in such a small quantity that it will not be useful to make a time machine. After some research, it is said that it is possible to make a time machine even without this specific substance. To do this, make a ball of ordinary matter and make a hole in the shape of a donut in the middle of it Vacuum will be created in the hole and the space-time frame will form a loop around itself. Then if a person rotates in this hole many times, he will reach the past.
But, this is just a theory. And it is very difficult to turn this theory a reality.
Objections to time travel
There are some problems with time travel, one of which is that if a person goes to his past, can he correct the mistakes of his past? And if so, what are the implications for the future? It's like a man going to his past and killing his great-grandfather. That is, it is impossible for this person to be born in the future when the great-grandfather is dead. Another such example is the recent pandemic. Suppose you go back in time and stop this pandemic from spreading. So where did all, that has happened so far as a result of this pandemic come from?
After much research, scientists have come to the conclusion that you cannot change the past. Even if you go to the past, what is to happen will continue to happen. If not in one form, then in another, so you cannot change your past.
Time Traveling claims
So far, many time travel claimants have emerged. Usually, these people write fake stories of their time traveling on the internet and get people's attention. A similar incident took place in the year 2000 when a person wrote on the internet that he came from the year 2036, He kept posting messages on the internet for a while, and then one day he suddenly disappeared. Similarly, another person claimed in the same year that he came from the year 2582.
He says that in 2026, the whole world will be plunged into darkness for three days.
Another interesting story is from Santiago Airlines. Santiago Airlines Flight 513 departed for Brazil. Halfway through the journey, the plane disappeared. Even after many attempts, no trace was found and it was thought that the plane had sunk in a sea. But then in 1989, a suspicious plane was suddenly seen flying near an airport in Brazil. And the plane landed at the airport without permission.
It was the same plane that flew from Santiago in 1954. From where did this plane appear 35 years later? Some people call it a time dilation event because something might happen that slowed down the time in the plane while 35 years had passed on Earth. Surprisingly, the condition of the plane was brand new. However, when the doors of the plane were opened, everyone inside had changed into a skeleton, even the pilot
Some people raise many objections regarding the truth of this incident, it has not been proved by any scientific evidence. Whether it really happened or it is just a story, no one knows.
Time travel research is still ongoing. This is a complex topic and different scientists have different opinions on it. There have been many films about it, including Interstellar, The Terminator, Back to the Future, and Doctor Strange.