2017
Gravitational Waves
Rainer Weiss, Barry C. Barish & Kip S. Thorne
About This Prize
The 2017 Nobel Prize in Physics was awarded to Rainer Weiss, Barry C. Barish, and Kip S. Thorne “for decisive contributions to the LIGO detector and the observation of gravitational waves.” On September 14, 2015, the twin LIGO detectors captured the signal GW150914 — ripples in spacetime produced by the merger of two black holes roughly 30 solar masses each, over a billion light-years away. This landmark detection confirmed a prediction Einstein made in his general theory of relativity a full century earlier, opening an entirely new window on the universe.
Rainer Weiss
“LIGO and Gravitational Waves I”
Barry C. Barish
“LIGO and Gravitational Waves II”
Kip S. Thorne
“LIGO and Gravitational Waves III”
Key Concepts
- • Laser Interferometer Gravitational-Wave Observatory (LIGO): Twin 4 km Michelson interferometers in Louisiana and Washington state, capable of detecting sub-atomic displacements
- • First Detection GW150914: Merger of two ~30 M☼ black holes observed on September 14, 2015, producing a characteristic chirp signal
- • Strain Sensitivity h ~ 10⁻²¹: LIGO measures length changes smaller than one ten-thousandth of a proton diameter, an extraordinary feat of precision engineering
- • Confirmation of Einstein’s 1916 Prediction: Gravitational waves were predicted by general relativity 100 years before their direct detection