For a long time now we have been hearing theories about time travelling but the final thought that often crosses our mind is that is it really possible to travel back in time?
To answer this question, we must be a bit more specific about what we mean by traveling through time. Discounting the everyday progression of time, the question can be divided into two parts: Is it possible, within a short time (less than a human life span), to travel into the distant future? And is it possible to travel into the past?
“Our current understanding of fundamental physics tells us that the answer to the first question is a definite yes, and to the second, maybe.
“The mechanism for traveling into the distant future is to use the time-dilation effect of Special Relativity, which states that a moving clock appears to tick more slowly the closer it approaches the speed of light. This effect, which has been overwhelmingly supported by experimental tests, applies to all types of clocks, including biological aging.
NASA’s space telescopes also give us a way to look back in time. Telescopes help us see stars and galaxies that are very far away. It takes a long time for the light from faraway galaxies to reach us. So, when we look into the sky with a telescope, we are seeing what those stars and galaxies looked like a very long time ago.
However, when we think of the phrase “time travel,” we are usually thinking of traveling faster than 1 second per second. That kind of time travel sounds like something you’d only see in movies or science fiction books. Could it be real? Science says yes!
More than 100 years ago, a famous scientist named Albert Einstein came up with an idea about how time works. He called it relativity. This theory says that time and space are linked together. Einstein also said our universe has a speed limit: nothing can travel faster than the speed of light (186,000 miles per second).
What does this mean for time travel? Well, according to this theory, the faster you travel, the slower you experience time. Scientists have done some experiments to show that this is true.
For example, there was an experiment that used two clocks set to the exact same time. One clock stayed on Earth, while the other flew in an airplane (going in the same direction Earth rotates).
After the airplane flew around the world, scientists compared the two clocks. The clock on the fast-moving airplane was slightly behind the clock on the ground. So, the clock on the airplane was traveling slightly slower in time than 1 second per second.
Now there also have been stories and some shocking events that suggest time travelling is real. But till date we don’t know the exact answer to this.
It is very likely that the laws of physics rule out macroscopic time machines, but possible that spacetime is filled with microscopic time loops.
That’s it for today.