First direct detection of gravitational waves by LIGO

In 1916, the year after the final formulation of the field equations of general relativity, Albert Einstein predicted the existence of gravitational waves.

Now, on 11 february 2016,  the detection of gravitational waves has been announced and the results have been published by Physical Review Letters.

The full article’s pdf from is available here


Phys. Rev. Lett. 116, 061102 – Published 11 February 2016


Observation of Gravitational Waves from a Binary Black Hole Merger

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0 \times {10^{ - 21}}. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410_{ - 180}^{ + 160} Mpc corresponding to a redshift z=0.09_{ - 0.04}^{ + 0.03}. In the source frame, the initial black hole masses are 36_{ - 4}^{ + 5}M⊙ and 29_{-4}^{+4}M⊙, and the final black hole mass is 62_{-4}^{+4}M⊙, with 3.0_{-0.5}^{+0.5}M⊙{c^2} radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.