They’ve called not one press conference but three of them, at least. Simultaneous events are now scheduled for Thursday in Washington, D.C., London, and Paris, and it seems like more are being announced every hour. We can assume the scientists of the Laser Interferometer Gravitational-Wave Observatory (LIGO) have something important to tell us.*
As you've probably heard, rumor is that LIGO has detected gravitational waves, possibly ones caused by the merger of two stellar-mass black holes. (The merger of two neutron stars or a particularly violent supernova could also send ripples through spacetime that LIGO could detect.) Kip Thorne, Caltech general-relativity guru and arguably LIGO’s most prominent supporter, has explained many times over the years why a discovery like this would be exciting, but the line of his I like best comes from 300 Years of Gravitation (1987): “If cosmic gravitational waves can be detected and studied, they will create a revolution of our view of the universe comparable to or greater than that which resulted from the discovery of radio waves.”
I like that line because it’s the opposite of cautious academic equivocating—and yet it’s published in a scholarly volume of essays by giants like Stephen Hawking, Roger Blandford, Roger Penrose, and Martin Rees. In a venue discouraging of hype, Thorne predicted that gravitational waves would transform our understanding of nature. This press conference on Thursday might be kind of a big deal.
The opening of the radio sky, of course, led to the discovery of radio galaxies, quasars, and astrophysical black holes. The detection of gravitational waves could be similarly transformative because it would mark the beginning of an era in which scientists can use gravitational waves just as they use electromagnetic radiation—as a means of observing the cosmos.
Naturally, I’m particularly interested in what this could mean for the study of black holes. The next few years already look incredibly promising; as early as next spring, the Event Horizon Telescope should start looking for the “shadow” of the black hole at the center of the Milky Way, meaning we might soon see, with actual pictures, the faces of these things. Adding gravitational-wave detectors to the toolbox is like growing a new sense organ. We’ll find out Thursday whether this organ has heard anything yet.
*Although wouldn’t it be funny if the press conference turned out to be a routine update?