The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo group confirmed that the waves came from a black hole merger by comparing their data with a theoretical model developed at Cornell.
Saul Teukolsky stated: "The LIGO announcement describes one of the greatest scientific discoveries of the past 50 years. Gravitational waves have been a theoretical prediction of Einstein's general theory of relativity for the past 100 years."
"Our group has been solving Einstein's equations on supercomputers to predict the precise form of the signal that should be seen. Our theoretical predictions lie right on top of the experimentalist's measurements - an exciting confirmation of general relativity."
"Finally these waves have been detected on Earth with an unbelievably sensitive experiment. And, surprisingly, the source of the waves is a system of two black holes in orbit around each other, that spiral inward and smash together."
This computer simulation shows the collision of two black holes, a tremendously powerful event detected for the first time ever by the Laser Interferometer Gravitational-Wave Observatory, which detected gravitational waves as the black holes spiraled toward each other, collided and merged. This simulation shows what the merger event would look if humanity could somehow travel for a closer look. It was created by the Cornell-founded Simulating eXtreme Spacetimes (SXS) project.
Credit: Simulating eXtreme Spacetimes Project
Led by scientists from the LIGO collaboration at the California Institute of Technology and the Virgo group collaboration, research published February 11 inPhysical Review Lettersreports the detection. The waves result from two black holes spiraling in toward one another and smashing together.
Until now, this scenario had only been predicted theoretically. Many astrophysicists doubted that it would occur often enough ever to be detected. However, soon after LIGO detectors in Livingston, Louisiana, and Hanford, Washington, were upgraded last summer, in September scientists found two black holes - each about 35 times the mass of our sun - moving at more than half the speed of light, orbiting each other and creating waves. Researchers spent the autumn confirming results.
"You need big computers because the equations are so complicated", explained Larry Kidder, senior research associate and a co-leader of the SXS collaboration. One calculation - with varying masses and spin rates - takes a supercomputer a full week to solve, running 24 hours a day. With different parameters, some calculations take months. SXS created a theoretical catalogue of what the different possible gravitational waves would look like.
Saul Teukolsky said that the new LIGO paper shows the measured waves with an SXS wave superposed on top and in excellent agreement with the measurements. "That's a very strong confirmation that these are gravitational waves that come from black holes - and that Einstein's general theory of relativity is correct", he stated.
With the LIGO confirmation of direct detection of gravitational waves, "This is a theorist's dream, the best possible source (two black holes) you could have", Saul Teukolsky stated.
On the news from LIGO, Saul Teukolsky explained: "This is something I've been working on ever since I came to Cornell. This is probably the most exciting episode in my professional career."
In addition to Saul Teukolsky and Larry Kidder, contributing to the Cornell work were research associates Michael Boyle and Scott Field, and graduate students Andrew Bohn, Francois Hebert and William Throwe.