Physics Colloquium: Listening to the cosmic chirping chorus with gravitational waves.

Event Details

  • Speaker(s): Samaya Nissanke
  • Date:
  • Time: 3 pm
  • Location: Science Complex, Atrium Wing, Rm. 1511

Together with the considerable advancement in numerical simulations of binary black hole mergers over the past three years, currently operational and near future gravitational wave detectors herald an unprecedented new era of gravitational wave astronomy. Accurate source modelling, in the form of theoretical gravitationl wave templates, for the inspiral and merger of compact binaries (neutron stars or black holes) is a prerequisite for detection and measurement by such interferometers. This seminar will introduce briefly gravitational wave detectors and review our current knowledge of gravitational wave forms for such sources. In particular, the talk concentrates on the gradual post-Newtonian described inspiral (where orbits shrink due to gravitational radiation and lose eccentricity) of the two bodies and their subsequent plunge and merger modelled using numerical relativity. Turning to gravitational wave astronomy, we discuss the role of such gravitational wave sources as a tool for probing cosmology using a network of advanced ground-based interferometers. By observing the inspiral of such systems, it is possible to measure an absolute distance to the sources. When coupled with independent electromagnetic measures of the redshift, these "standard sirens" enable precision estimates of cosmological parameters, such as dark energy and Hubble's parameter. Finally, we examine the large recoil kicks of the final black hole, exhibited by numerous recent numerical simulations, from the merger of asymetric black hole binaries with initial high spins and specific spin orientations.