More than fifty years ago, the objective of directly detecting a curious phenomenon that Albert Einstein called “gravitational waves” was established and that sought to open a new window to the universe to understand it in a more precise way.
Well, in the centenary year of the theory of general relativity, specifically on September 14, 2015, a group of scientists has managed to directly observe these waves, a discovery that has just been confirmed in recent weeks. But, beyond the joy of astronomers, many wonder what, in reality, the “gravitational waves“?
To understand them, we will have to make an effort: imagine the universe as the surface of an immense lake that is altered by different elements, such as a stone thrown into the water or a fish rising to the surface.
Every time something moves or breaks through the surface, it generates waves that scatter around and can go very far. These waves depend on the size and movement, so that a swimming duck would create many more waves than a simple stone, and they would go further.
In the same way, all the great celestial bodies generate waves in the universe based on their mass that behave in a similar way to the waves of the lake. The largest, such as black holes and galaxies, are the ones that generate gravitational waves larger, which can reach the speed of light and whose distortions generate a kind of echo in the universe that we have been able to detect, in the same way that we could know that something moves in the center of the lake by observing only the waves reaching the shore.
Finding these waves is so important because, although it may not seem like it, they help us travel through time … In the astronomical sense, of course.
For example, in the same way that if we see a lightning in the distance and then we hear the thunder we know that the sound has arrived late and was produced by a lightning that no longer existed at the time of hearing it, the gravitational waves have to travel distances so gigantic that, when they reach us, they may be reflecting objects that disappeared millions of years ago, so that we can study what the universe was like before we lived in it, like a kind of “space archaeologists”.
However, we do not have to go that far to find gravitational waves, since any object, no matter how small, is continuously generating them. The Earth, an airplane, or even two dancing people are distorting the calmness of the gravitational lake surface, only, in their case, the waves they generate are so small that they are insignificant (and, for us, undetectable) next to the waves. generated by the great stellar bodies and that have been, for the first time in history, observed by the human being … One hundred years before they told us about them.
Einstein, you were right.
Dew DCR
