Surfing the LIGO wave, sounding out black holes and more

By Matin Durrani and Tushna Commissariat

Unless you are completely disconnected from all electronic media, the Internet and don’t read a newspaper, by now you must have heard that the LIGO Virgo collaboration has made the first ever detection of gravitational waves, spewed out by two black holes merging into one. The story made waves across the world, if you will excuse the pun, and seemed to capture the interest of scientists and the public alike. Above you can listen to the chirp of the merger event, dubbed GW150914, that occurred 1.3 billion years ago, when multicellular life was just emerging on Earth. Indeed, these sounds are so intriguing that they are being turned into musical compositions.

Theoretical physicist Lawrence Krauss, who is director of the Origins Project at Arizona State University, has written a succinct synopsis of yesterday’s discovery and its implications in The New York Times, stating that in addition to letting us explore exotic features of black holes, the discovery could shed light on the evolution of galaxies, stars and gravity – and may even let us observe gravitational waves from the Big Bang.  He also rightly praises the technological power of the LIGO detectors, which can measure a periodic difference in the length between two tunnels by a distance of less than 1000th the size of a single proton. “This difference is so small that even the minuscule motion in the position of each mirror at the end of each tunnel because of quantum-mechanical vibrations of the atoms in the mirror could have overwhelmed the signal,” Krauss writes. “But scientists were able to resort to the most modern techniques in quantum optics to overcome this.” Forget any possible immediate applications, like faster cars or better toasters, though. For Krauss, yesterday’s discovery is also about “the persistent curiosity and ingenuity of humankind — the qualities that we should most celebrate about being human”.

Rumours about the discovery, which was actually detected on 14 September last year, have been floating around ever since – indeed, the first big rumour came from Krauss himself back in September, but the LIGO collaboration remained firm – the researchers would only talk about their result when it was peer reviewed and published, which only happened yesterday. But big secrets have a way of getting out and by last week almost everyone was aware that the team had some big news to reveal and may scientists and journalists were actually aware of the results. Rather comically, for some, the secret was out 15 minutes before the official announcement at the DC press conference, thanks to a picture of a cake Tweeted by NASA scientist Eryn Lee Ryan!

Over at the National Geographic website, science journalist Nadia Drake explains just why it can be difficult and frustrating to quickly and clearly report on a finding that has persistent rumours about it before any confirmed news is out. Physics World‘s Margaret Harris also talked about this in her blog yesterday, where she looks into the openness and transparency of the scientific process.

And finally, if you are keen to polish up your knowledge on gravitational waves some more, sign up for this upcoming Future Learn MOOC on “Gravity! From Big Bang to black holes”.