Gravitational Wave Matched Filtering

Matched filtering is a signal processing technique used to detect gravitational waves by correlating detector data with theoretical waveform templates. When two massive objects (black holes, neutron stars) merge, they emit gravitational waves that pass through Earth, producing tiny distortions in laser interferometers like LIGO and Virgo. Matched filtering, formalized by Harry Nyquist, optimally extracts these signals from noise, enabling the detection of mergers billions of light-years away.