Feb 26, 2023
Finding Nonlinearities in Black Hole Ringdowns
Posted by Saúl Morales Rodriguéz in categories: cosmology, evolution, physics
Simulations show that nonlinear spacetime dynamics manifest in the postmerger gravitational-wave signal of binary black hole coalescence.
“Spacetime tells matter how to move; matter tells spacetime how to curve.” This statement by physicist John Wheeler captures a defining feature of general relativity: its prediction of nonlinear spacetime dynamics. Such nonlinear evolution should be most evident in energetic spacetime events such as merging black holes, prompting the question of whether we can test for it using observations of gravitational waves emitted during such mergers. Two independent teams, led by Keefe Mitman at the California Institute of Technology [1] and Mark Ho-Yeuk Cheung at Johns Hopkins University in Maryland [2], show that this is the case. Using numerical simulations, they show the presence of nonlinearity in postmerger gravitational-wave signals.