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.

When Scientists Made the 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 gravitational waves in an instrument on Earth. In so doing, they have 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 signals and determined their cosmic source. According to calculations, the gravitational waves are the product of a collision between two massive black holes located 1.3 billion light years away — a remarkably extreme event that has never been observed until now. Read the press release

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

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 in 1915, they escaped direct detection for a century. LIGO was designed to register the astonishingly tiny effects of passing gravitational waves here on Earth using a precise arrangement of mirrors, lasers, monitoring equipment and other advanced technologies. In February 2016, LIGO researchers announced the long-awaited, 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 swell 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, like accelerating black holes or neutron stars. The ability to measure the strength and frequency of gravitational waves is critical because such measurements provide vital details about the distant, exotic phenomena that unleashed the waves upon the cosmos. 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 offers a new window into events, such as the collisions of black holes, and the explosions of titanic stars, 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 at any given time are part of the LSC. LIGO is funded in part by the National Science Foundation. Learn more