The Dhaka Times Desk How many things will be discovered in the world for ages. Scientists have read this time about the 'black hole', the biggest devourer of space. What is a 'black hole'?
It took scientists years to figure out how the gravitational force actually acts on light particles. If a star is large enough, if its density is fixed, the particles of light emitted from it cannot escape from the star. Under the influence of the star's gravitational force, it will return to the star again. It's a lot like throwing a tennis ball into the void. If light cannot escape, not only that, but the star will not be visible to us.
Now the question may come, if the black hole is not seen, then how can you believe that there is a 'black hole'? But faith is not important, evidence is important.
Now the question is, is the 'black hole' theory wrong, or is it Einstein's theory..? The truth is that neither is wrong. The exact solution is in Einstein's Special Theory of Relativity.
In his theory, Einstein said that when a massive object like a star passes by, the path of light is bent. The same thing happens in black holes. There is no way that the light of a distant star will fall on the black hole. The light bends under the influence of the gravitational force of the black hole, as if the light has no courage to touch the body of the black hole!
For example, suppose A is the far beam and B is the near beam. A bends as it passes the blackhole's gravitational limit. B, on the other hand, is entering the gravitational field, but is unable to escape. The beam of light coming from a distant star and bent before touching the body of the black hole is the white rod of the scientists. It is the nature of this bent light that essentially heralds the existence of 'black holes'.
Interestingly, when Einstein published his General Theory of Relativity, many people did not accept it. Then there is a need to prove it practically. In such a situation, a group of scientists decided to test it. That is, the path of light bends when it passes by a massive object or star. They divided into two groups and went to the two ends of the world with various scientific instruments. Then on the day of the solar eclipse, both groups were put to the test. In this test conducted separately, the results of both groups came out the same. That is, Einstein's prediction is correct, because of this experiment, the team of scientists became famous overnight.
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