When black holes collide, the impact radiates into space like the sound of a bell in the form of gravitational waves. But after the waves, there comes a second reverberation—a murmur that physicists have theorized but never observed.
An international collaboration has for the first time simulated in detail what these whispers—called late-time gravitational wave tails —might “sound” like.
“So far, we’ve only seen tails in simplified models, not in full simulations of numerical relativity,” said Leo Stein, University of Mississippi associate professor of physics and astronomy and co-author of the study. “These are the first fully numerical simulations where we saw tails clearly.”









