“Ladies and gentlemen: we have detected gravitational waves.” This is how the science portion of the press conference began on Thursday. What a monumental day for science!
Is this the discovery of the year, of the decade, or of the century, and what is this discovery anyway? Scientists with the Laser Interferometer Gravitational wave Observatory (LIGO), “felt” or even actually “heard” the spacetime in which the Earth and the whole universe is embedded in give only clear “ring” almost like that of a telephone.
The ring made a distinct sound which is unique only to that of the collision of two large black holes that took place in another galaxy. Ok, and what is the excitement all about? Well 100 years ago Einstein asserted that the planets, the stars, and the galaxies are all making indentations in the space in which they live. He further said that they would “feel” each other’s presence by communicating by these rings, or ripples in space.
While it looks to us like the Earth, the Sun and all the stars more or less sit in empty space, Einstein says they are actually making indentations in the fabric of spacetime. This is analogous to how a heavy metal ball will make an indentation in a rubber sheet held aloft and taut.
This is also analogous to how a diamond ring may seem to hover on your finger, but it is actually set into a more dull metal ring. Here the planets and stars are the gems and space is the ring. This idea of Einstein’s is fascinating, and seemed to work better than any other idea, and yet we had no proof. As of three days ago the proof arrived, and interestingly, it came at audible frequencies.
LIGO now enables us to have ears that are open now to the actual sound of the universe. Last week, we were deaf, and now we can hear! What will come next? What will we do with this newfound sense? Please stay tuned. Even though LIGO took ~2 decades to build, it only just turned on for taking scientific data officially in October, 2015. This adventure is only just beginning.