British physicist Stephen Hawking says the detection of gravitational waves provides a completely new way of looking at the universe, and is at least as important as the detection of the Higgs boson at the Large Hadron Collider.
The results reported by the Laser Interferometer Gravitational-Wave Observatory mark the first-ever observations of a black hole merger, and the first of what’s expected to be many observations of gravitational waves. “The ability to detect them has the potential to revolutionize astronomy,” Hawking told the BBC after LIGO’s announcement on Thursday.
The waves are ripples in the fabric of spacetime, set off in the course of gravitational interactions. Their existence was predicted by Albert Einstein’s general theory of relativity a century ago, but until now, no instruments were sensitive enough to detect them. LIGO uses two sets of L-shaped detectors in Hanford, Wash., and Livingston, La. Each detector takes advantage of finely tuned, cross-interfering lasers to register distortions in spacetime that are tinier than one ten-thousandth of the size of a proton.
In addition to confirming a key claim of general relativity, LIGO’s readings provide the best evidence to date that black holes actually exist.
https://www.youtube.com/watch?v=Z0E6UUmJLdg
LIGO’s scientists traced the signals they saw to the merger of a black hole 29 times as massive as the sun with another black hole 36 times as massive as the sun. The resulting black hole amounted to 62 solar masses, with the equivalent of three suns converted into gravitational-wave energy.
Hawking said the findings confirm his theoretical work from decades ago, including the claim that the area of the merged black hole should be greater than the sum of the areas of black holes that were merged. Eventually, observations of a variety of black hole events could provide more precise estimates of cosmic distances, he said.
But LIGO’s observations also pose a puzzle: Hawking said the black holes that collided were each more massive than what would be expected to result from the collapse of a star. “So how did both of these black holes become so massive?” Hawking asked.
Here’s what Hawking had to say about the discovery on Facebook, plus other reactions from Twitter:
My congratulations to the LIGO team on their discovery of gravitational waves. It is a result that is at least as…
Posted by Stephen Hawking on Thursday, February 11, 2016
Einstein was right! Congrats to @NSF and @LIGO on detecting gravitational waves – a huge breakthrough in how we understand the universe.
— President Obama (@POTUS44) February 11, 2016
OSTP Dir Holdren on the groundbreaking detection of gravitational waves. Congrats to @NSF & all behind the effort! → https://t.co/KO7WBz5Qxs
— White House OSTP 44 (@WHOSTP44) February 12, 2016
Gravitational Waves https://t.co/4a9n0czB4a https://t.co/Hn233yY15B pic.twitter.com/E340a2lyKM
— XKCD Comic (@xkcdComic) February 11, 2016
#LIGO scientists discovered Einstein’s gravitational waves…but what are they? Find out here: https://t.co/KMOJgmtqkA pic.twitter.com/gR7kyeUPRt
— NASA (@NASA) February 11, 2016
WATCH NOW: @neiltyson explains Einstein's Gravitational Waves Theoryhttps://t.co/lmVv1gHDyh @StarTalkRadio
— The Cumia Show (@TheCumiaShow) February 12, 2016
Why care about LIGO? My opinion piece for @nytimes Sunday Review "Finding Beauty in the Darkness" now up online: https://t.co/vxzLXBdUov
— Lawrence M. Krauss (@LKrauss1) February 11, 2016
What does a collision between two black holes sound like? https://t.co/NUeY886fQP #LIGO pic.twitter.com/uDKKoDdbHK
— The New Yorker (@NewYorker) February 11, 2016