TAPIR Seminar
John Friedman received his B.A from Harvard College in 1967 and his Ph.D from the University of Chicago in 1973, supervised by Nobel laureate S. Chandrasekhar. From 1974 to 1976 he was a Fermi Fellow at the University of Chicago. Since 1976 he has been at the University of Wisconsin-Milwaukee, where Friedman served for three years as Chair of the Department of Physics and where he currently holds the rank of University Distinguished Professor Emeritus. Friedman is a Fellow of the American Physical Society and a former chair of its gravitational physics section. He has served on the editorial boards of several prestigious journals, including Classical and Quantum Gravity, Physical Review Letters and Physical Review D. Professor Friedman is currently a U.S. representative to the International Society of General Relativity and Gravitation.
Gravitational waves from the inspiral of a stellar-size black hole to a supermassive black hole can be accurately approximated by a point particle moving in a Kerr background. At first order in the ratio of the masses, one must renormalize the perturbed metric to compute the deviation of the particle's path from a geodesic of the Kerr geometry. The talk presents progress on computing the particle's acceleration ("self-force") in a gauge that is constructed from the gauge-invariant Weyl tensor -- from the solution to the Teukolsky equation. Along the way, a computation of essentially gauge-invariant quantities allows one to find currently inaccessible parameters in the post-Newtonian expansion of of the energy and energy-flux of a compact binary. Remarkably, we are able to extract analytic parameters from numerical computations that are accurate to better than one part in 10225.