The Laser Interferometer Gravitational-Wave Observatory (LIGO)

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SPECIAL ROUNDTABLE: Three LIGO researchers discuss the monumental findings that will open up an entirely new era of scientific investigation.


NEWS: Scientists Make First Direct Detection of Gravitational Waves

For the first time, scientists in the LIGO Scientific Collaboration — with a prominent role played by researchers at MIT and Caltech — have directly observed the ripples of gravitational waves in an instrument on Earth. In so doing, they have again dramatically confirmed Einstein’s theory of general relativity and opened up a new way in which to view the universe. But there’s more: The scientists have also decoded the gravitational wave signal and determined its source. According to their calculations, the gravitational wave is the product of a collision between two massive black holes, 1.3 billion light years away — a remarkably extreme event that has not been observed until now. Read press release

What is the Laser Interferometer Gravitational-Wave Observatory (LIGO)?

Einstein's Messengers is an award-winning documentary on LIGO, NSF's Laser Interferometer Gravitational Wave Observatory. (Credit: National Science Foundation)

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is an ambitious physics experiment designed to measure gravitational waves reaching our planet from deep space. Gravitational waves are elusive ripples in the fabric of the universe. First predicted to exist a century ago, they have never been directly detected. LIGO is designed to register the astonishingly tiny effects of passing gravitational waves here on Earth using a precise arrangement of mirrors and lasers, monitoring equipment and other advanced technologies. In February 2016, LIGO researchers announced the first-ever direct sensing of gravitational waves. Learn more

What are gravitational waves?

Physicists Umberto Cannella and Daniel Whiteson explain what gravitational waves are and why they'll cause a big ripple in our understanding of the Universe. (Credit: PHD Comics)

Gravitational waves are a key prediction of general relativity, a theory proposed by Albert Einstein in 1915 that is still our best explanation for the force of gravity. Einstein pictured space and time as interwoven aspects of the same underlying reality, known as space-time. Objects that possess mass, such as stars and planets, warp space-time much like how a heavy ball placed on a trampoline creates a bowl-like depression around itself. This curvature in the space-time trampoline, so to speak, is experienced by all matter in the universe as the force of gravity. Whenever any mass moves, it generates gravitational waves that ripple through space-time like ripples radiating across a pond's surface. For these waves to be big enough to detect, however, extraordinarily massive, astronomical objects are required, such as accelerating black holes or neutron stars. The ability to measure the strength and frequency of gravitational waves is important because such measurements would provide vital details about the distant, exotic phenomena that produced them. Learn more

Why are gravitational waves important for science?

Virtually all of our knowledge about the universe has come to us in the form of light, or electromagnetic radiation. Gravitational waves, however, are an entirely different form of radiation, produced by some of the most violent events in the universe. The study of gravitational waves will offer a new window into the explosions of titanic stars and events, such as the collisions of black holes, which may not produce significant electromagnetic radiation. Gravitational waves should even be able to let scientists see all the way back to the origin of the universe itself in the Big Bang. Learn more

What is The Kavli Foundation's role in LIGO?

The Kavli Foundation supports the Massachusetts Institute of Technology's (MIT) Kavli Institute for Astrophysics and Space Research (MKI). MIT and the California Institute of Technology (Caltech) operate LIGO on behalf of a global research community called the LIGO Scientific Collaboration (LSC), which includes members from more than 80 scientific institutions worldwide and more than 900 scientists. About three dozen MKI members are part of the LSC. LIGO is funded in part by the National Science Foundation. Learn more

Selected News Stories

Signal was produced by two black holes colliding 1.4 billion light years away.

The project will expand the international network of gravitational wave detectors.

LIGO signal reveals first observation of two massive black holes colliding, proves Einstein right.

Three principal researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO)—Nergis Mavalvala, Rainer Weiss and Matthew Evans—reflect on the epic discovery of gravitational waves and how it will transform the way we see the cosmos.

The Advanced LIGO begins operations this week, after 7 years of enhancement.