What are gravitational waves? A 90-second explainer

11 Feb 2016

Gravitational waves are getting an awful lot of news coverage of late, but what are they? This explainer video tells all.

Apparently we’re in “a new era in astronomy and physics”, with the expected imminent announcement of the discovery of gravitational waves set to completely revolutionise the field.

So says theoretical physicist and cosmologist Laurence M Krauss, whose cryptic tweet kicked off a discussion in the media that most people are, surely, confused by.

What are gravitational waves? Well, basically speaking, they form part of Albert Einstein’s General Theory of Relativity.

Last November was the 100th anniversary of Einstein presenting his theory and, for those unaware of the detail, here’s former Doctor Who David Tennant explaining all.

Gravitational waves were originally believed to be the result of extreme cosmic events like the collision of two black holes, or the birth of a supernova and, if they are proven to exist, it will provide an opportunity to measure the origin of the universe in a completely new way.

For those who simply want a 90-second explainer on gravitational waves, though, here’s ESA LISA Pathfinder project scientist Paul McNamara, with a marble, a sheet and a cube.


“These waves are streaming to you all the time and, if you could see them, you could see back to the first one trillionth of a second of the Big Bang,” said NASA’s Gravitational Astrophysics Lab chief Tuck Stebbins.

To add even greater emphasis, he added that “we stand at a threshold of a revolutionary period in our understanding, our view of the universe”.

Gravitational waves image via Shutterstock

Gordon Hunt was a journalist with Silicon Republic