Black holes ring like colossal bells. Colliding or devouring matter, they oscillate and send ripples through the cosmos — gravitational waves. These are tremors of the very fabric of spacetime, and their tone reveals the hole's inner structure.
Conventional gravity theory considers only instantaneous spatial curvature. But scientists employed nonlocal gravity — an approach where gravity remembers the entire past of the universe, much like a bell retains the echo of a distant strike. They derived equations for any spherical black hole in this theory and computed the oscillations of solutions that slightly deviate from the classic Schwarzschild hole.
For the first time, a complete framework for analyzing nonlocal black holes has been developed. Their gravitational voice may be a direct route to solving the mystery of dark energy.
In nonlocal gravity, a black hole's pull takes into account the entire history of the cosmos — its field 'remembers' events from billions of years ago. That's why the gravitational ringing sounds like an echo of the Big Bang.
In 'Interstellar,' the heroes dive into a black hole, but in reality, we might hear its voice — gravitational waves will tell us about dark energy and maybe even about other universes.