University of Maryland
The latest gravitational-wave discovery from LIGO and Virgo
The 2015 detection of gravitational waves by the Advanced LIGO detectors was a long-awaited milestone. Besides confirming a prediction of Einstein's general theory of relativity (GR), the discovery revealed a new and largely unexpected class of astronomical systems -- heavy black hole binaries -- and also enabled detailed tests of GR. Additional detections have followed from the rest of the first Advanced LIGO observing run plus the second observing run, in 2016-17. In August 2017, the Advanced Virgo detector in Italy joined LIGO for the last month of the observing run. In September, the LIGO and Virgo teams announced the fourth high-confidence binary black hole merger detection, which was especially notable since the Virgo data allowed the sky position of the source to be localized much better than previous events. And just this past week, LIGO and Virgo announced the long-awaited detection of a binary neutron star inspiral and merger, which was followed in spectacular fashion by a short gamma-ray burst and kilonova/afterglow emissions across the whole electromagnetic spectrum. I will discuss the latest gravitational-wave detection and its implications for astrophysics and fundamental physics.