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"Observing Love, memory, and spin with gravitational waves", department colloquium, January 23, 2012, 10-11am

Marc Favata, UW-Milwaukee/Caltech

Gravitational-waves are ripples in the curvature of spacetime produced by compact objects (especially neutron stars and black holes) moving at relativistic speeds. In the next 5 years, LIGO (the Laser Interferometer Gravitational-wave Observatory) and its international partners expect to make the first direct detections of these waves (primarily from stellar-mass neutron star or black hole binaries). Future space-based detectors will observe lower-frequency gravitational-waves from supermassive black holes and white dwarfs. Extracting the most science from the expected signals requires detailed modeling of numerous physical effects.  After a brief review of general relativity and gravitational waves, I will discuss a few examples of these effects, including: (i) the nonlinear gravitational-wave “memory” in binary black hole mergers, (ii) the tidal “Love number” in binary neutron stars, and (iii) spin interactions in black hole binaries with very small mass ratios.