Gravitational Waves – Belated Post

I am well aware that these were discovered (well, their existence was officially proved) a few weeks ago but I’ve been really rather busy these past few weeks dealing with the irrelevant time consuming project that is my Mock Exam Fortnight and all the stress and comfort eating that it entails. While lying on the sofa basking in self pity one has when blessed with the sort of cold that makes you occasionally forget about the presence of your nose, I sat staring at my phone waiting for scientists to make the eagerly awaited announcement that these waves are, in fact, the real deal, and that Einstein is even more of a genius lad than we had thought.

So, what are gravitational waves?

My knowledge (and enjoyment) of physics is basic at best, but when it comes to astronomy I am a bit of a nerd. My very simple understanding of gravitational waves is that when an enormous gravitational event occurs, such as a star exploding, then these waves are produced, in the same way that ripples go across a pond when something happens in the water.

The waves that were picked up by scientists were produced when black holes that had been orbiting one another collided; black holes are so extremely dense and have such an enormous gravitational pull that for two to collide would (an did) have an enormous impact. This impact was gravitational waves, which actually compress the space they pass through, which, as I’m sure you can imagine, means they are pretty powerful.

How did they prove it?

Physicists built two 4km long tunnels with sensors at either end; these sensors could detect the shortening and lengthening of the tunnel when gravitational waves passed through them – and they did. And then scientists and nerds like me became hugely excited and enjoyed sharing the news to people who responded with blank faces until we explained what we were talking about.

I hope that has made things a bit clearer for people who had heard of these waves but didn’t know what they were, or has amused real scientists who can see that I know pretty much nothing when it comes to the Physics World.