The announcement indicates that gravity waves have been detected. The source of the waves is the collision of two black holes each with a mass of tens of times that of the sun. In the collision, an amount of mass was lost equivalent to several times that of the sun. This loss of mass was due to it being converted to energy that was expressed as gravity waves. It took an interferometer capable of measuring disturbances smaller than the nucleus of an atom to detect these gravity waves.
At the Wolfram blog, Jason Grigsby provides some background on the detection of gravity waves by LIGO.
Earlier today at a press conference held at the National Science Foundation headquarters in Washington, DC, it was announced that the Laser Interferometer Gravitational-Wave Observatory (LIGO) confirmed the first detection of a gravitational wave.
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A hundred years ago, Einstein’s theory of general relativity predicted the existence of gravitational waves—little ripples in spacetime that carry energy and information. But it has taken a century of technological progress to provide us the practical means to confirm the theory. LIGO’s historic discovery has not just confirmed Einstein’s theory—it also provides us with a first peek into an entirely new way of conducting astronomy.
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Given the vanishingly small earthly effects of gravitational waves, it takes some of the most energetic events in the universe to generate gravitational waves that are detectable by LIGO. The most likely to be detected are generated by binary black holes with a total mass of about 10–100 times that of the Sun. Indeed, we heard at the LIGO press conference earlier today that the detected waves were from the merger of two black holes of approximately 65 solar masses total. During the course of spiraling together and merging, three solar masses’ worth of energy were radiated out in a fraction of a second. The actual merger of these two black holes happened approximately 1.3 billion light years away, meaning that these two black holes merged before multicellular life came about on Earth.
That’s two major confirmations of theory in recent years and both get into fundamental questions about the structure of matter. Gravity and the Higgs Boson both star in string theories that try to combine everything we know into a unified model.