Gravitational waves exist! Gravitational Waves have been detected by the scientist at LIGO (Laser Interferometer Gravitational -Wave Observatory) by using two observatories based in Washington and Louisiana.
WHAT ARE GRAVITATIONAL WAVES?
Consider the empty void of space as a big bed sheet spread over the universe. This sheet is our “fabric” of space-time. Now place objects on this fabric and let their mass create “distortions” in the “fabric.” The heavy objects create larger distortions. While smaller objects wrap around them and simultaneously are under the influence of some other objects’ distortions. Now consider two really “heavy” objects kept somewhat close to each other. Slowly and gradually they slip closer towards each other because of the “distortions” or the “depression” created by the other object. As time passes, these objects eventually collapse into a single depression, made by their combined weight.
Referring to this bed-sheet analogy, we can consider the “two really heavy” objects like black holes which collided into one giant black hole which was supposedly 60 times larger than our sun.
The collision happened when the two constituent black holes were spiraling each other at the speed of light. They then emitted ripples of gravitational waves just after their collision. These are the waves that we have been looking for. The effect of these waves fade over distances, and this makes them tough to detect.
HOW WERE GRAVITATIONAL WAVES DISCOVERED?
A black hole merger is a phenomenon when two black holes orbit each other at high speeds (almost 30 times per sec) while accelerating and spiraling towards each other. Getting closer until they finally collapse into one single black hole. This collision causes the newly made black hole to wobble a little before taking a perfectly spherical shape. Eventually, this emits a burst of gravitational waves called ‘the chirp’. The event recorded at the LIGO lab detected waves emanating from one such merger which took place 1.3 billion years ago.
Professor Alberto Vecchio of Birmingham University explains the importance of gravitational waves by calling it transformational
Such an interestingly rare phenomenon of fusion of two black holes had been predicted but never observed before. The instruments at LIGO were fine tuned to detect sensitive ripples of the gravitational waves which passed through Earth making it contract and expand like a jelly blob but at a very minute level.
WHY IS THEIR DISCOVERY SO IMPORTANT?
The discovery of Gravitational Waves is no wonder, a vital one. When we discovered radio waves, we found a way to communicate. Almost all things in outer space that we were unable to see with telescopes were observable using radio waves. Residual electromagnetic waves from the Big Bang are still permeating through space. These waves tell us a lot about the creation of our universe. But the distant past where we seek answers today is inaccessible due to limitations in our methods of investigation. The discovery of gravitational waves opens up a whole new treasure chest of ways in which we can learn more about our universe. Mostly about dark matter.
This detection is significant in the world of science because of these reasons:
- These waves fit perfectly in the theory predicted by Einstein almost 100 years ago.
- Results were derived after detectors at LIGO measured distortion in space-time during a black hole merger from 1.3 billion years ago.
Watch the scientist announce their discovery here: