UWM Physicists Help Discover a Second Pair of Colliding Black Holes

Thirty University of Wisconsin – Milwaukee (UWM) physicists, members of the Leonard E. Parker Center for Gravitation, Cosmology & Astrophysics, as members of the international LIGO (Laser Interferometer Gravitational-Wave Observatory) and the Virgo scientific collaborations, have participated in the detection of a second pair of colliding black holes. UWM professors Patrick Brady, Jolien Creighton, Xavier Siemens, and Alan Wiseman, along with 26 UWM students and scientists assisted in the analysis of massive amounts of data from the two “Advanced LIGO” detectors located in Hanford, Washington, and Livingston, Louisiana. The gravitational waves detected by the LIGO observatories on December 26, 2015, were created when two black holes (with masses of about 14 and 8 times that of our sun) merged approximately 1.4 billion years ago.

The discovery of this second event has permitted a more precise test for violations of Einstein’s theory of general relativity. Gravitational waves offer an entirely new way to investigate the universe; complementing tradition observations made with forms of radiation, such as visible light, radio waves, and X-rays. The discovery, is described in an article published June, 2016 in the journal Physical Review Letters.

More information can be found at Gravitational waves detected from 2nd pair of colliding black holes.