Astrophysicists May Have Found Gravitational Waves. Or Not

All it took to get the physics community riled up was one tweet, from an Arizona State University astrophysicist named Lawrence Krauss:

It's understandable. Gravitational waves, if they exist at all, are pretty neat. Just like dropping a spoon into a bowl of Jell-O will make waves, so too does a black hole moving through space (or two black holes crashing into each other, or any number of other massive, catastrophic things). Except replace “Jell-O” with “the fabric of spacetime itself.”

LIGO can sense those wiggles. Its two L-shaped pairs of 2.5-mile-long tubes—one set in Hanford, Washington and the other in Livingston, Louisiana—bounce lasers along a series of mirrors. If a gravitational wave passes over Earth, it literally deforms local spacetime, so the tubes stretch and compress. That changes the path of the lasers’ light a tiny bit—a deviation that LIGO can detect.

Gravitational waves tell the story of the universe's mass. Every object from black hole to supernova, everything from black hole collisions (the most likely explanation for this potential LIGO discovery) to superfast expansion of the universe has its own gravitational fingerprint. From those swirls, astronomers will be able to learn about spacetime, gravity, and the objects themselves. And no one knows what they’ll find out. “The direct detection of gravitational waves will open new avenues to explore the universe, and as such, will almost certainly be revolutionary,” says Chiara Mingarelli, a theoretical astrophysicist at the California Institute of Technology in Pasadena, who studies gravitational waves but is not part of LIGO.

Exciting, right? Which is exactly why Krauss says he spoke out about the rumors. He had heard whisperings of a potential discovery from multiple sources and wanted to use his considerable social-media influence to bring some of the scientists’ fervor to everyone else, not to incite what he calls a media frenzy. “My intent was to get people more excited so if LIGO did make a discovery, more people would hear about it,” Krauss says.

And it worked. But it doesn't change the fact that nobody outside the lab knows whether LIGO found gravitational waves or not. In September a $200 million upgrade transformed LIGO into Advanced LIGO, with more sensitive detectors. But for now, LIGO isn’t talking. “We are still taking and analyzing data and have no reviewed results to report,” says Michele Vallisneri of the Jet Propulsion Laboratory in Pasadena California, who is a member of the LIGO collaboration.

A spokesperson for LIGO says much the same: “We were taking data until today,” says Gabriela Gonzalez. “We have been taking data for just four months. We have not finished analyzing the data or reviewing the results. We don't have anything to say.” Gonzalez did not have a timeline for when they'd provide evidence to support or refute the rumors, but she estimates it will be at least a month. Maybe two. “Unless,” she says, “we find things. And then it's difficult to predict how long it will take us to finish understanding everything we don't understand.”

In general, scientists are cool with that caution. “If they have made a detection, what’s the rush?” says Mingarelli. “Let them figure out if they do indeed have extraordinary evidence before making an extraordinary claim.” The team’s protocol is designed to make sure that any extraordinary claims will come with de rigueur extraordinary evidence.

That hasn’t kept the community from getting pretty excited about the idea. “I think everyone's ears perked up when they saw the rumors on Twitter,” says Peter Yoachim, an astronomer at the University of Washington. But their reaction would be less subdued if the rumors came with data to back them up. “If the paper was out, people would be popping champagne corks!” he says.

In a world filled with Internet, it’s productive to openly discuss results, let other scientists digest them in the public eye, and clue everyone else in on the excitement. “I know I prefer hearing rumors that are labeled as preliminary rumors, more than having people do ‘science by press release,’” says Yoachim.

If evidence bears the buzz out, Krauss says, “gravitational wave astronomy will be the astronomy of the 21st century.”

But the rumors can’t become more (or less) until the LIGO team is ready. “Facts are a lot more fun than rumors,” Gonzalez says, “and they will come soon enough.”