What are gravitational waves?
Einstein predicted them in 1916. We didn't detect them until 2015.
The answer
Gravitational waves are ripples in the fabric of spacetime caused by the acceleration of massive objects, predicted by Einstein's general relativity in 1916. When two black holes or neutron stars spiral into each other and merge, they produce gravitational waves that travel at the speed of light, stretching and compressing space as they pass. LIGO first detected them on September 14, 2015, from two black holes merging 1.3 billion light-years away. The detection measured a distortion of space smaller than one ten-thousandth the width of a proton.
Source: LIGO Scientific Collaboration
- gravitational waves
- LIGO
- general relativity
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