Description:

Abstract: LIGO and Virgo have observed over 80 gravitational-wave sources to date, including mergers between black holes, neutron stars, and mixed neutron star- black holes. The origin of these merging neutron stars and black holes remains unknown, with implications for stars, galaxies and cosmology. Fortunately, the gravitational waves from these mergers encode their masses, spins and distances, which in turn encode how, where and when black holes and neutron stars are made. I will review the latest LIGO-Virgo discoveries and explain how we extract astrophysical lessons from gravitational-wave data. I will then discuss some recent lessons, including mass gaps, evolution with redshift, and implications for cosmology. While the latest gravitational-wave observations have answered a number of longstanding questions, they have also unlocked new puzzles. I will conclude by discussing what we can expect to learn from future gravitational-wave and multi-messenger data.

Speaker: Maya Fishbach, Northwestern University