Quasinormal modes

Space Black hole ‘hair’ could reveal hidden matter after two black holes collide

A new framework shows how hidden black hole “hair” could leave separate fingerprints in the frequency and fading of gravitational waves.

Space Black Hole “ringing” could put Einstein’s theory to its toughest test Joshua Shavit

Space Faint black hole ‘ringing’ provides a sharper test of Einstein’s gravity Joseph Shavit