Binary Black Hole Mergers: Comparison of Numerical Relativity and Particle Perturbation Methods

Since the early 1970s much has been learned about black hole physics

from particle perturbation (PP) work, in which a black hole is

perturbed by a "particle." This approach is particularly well suited

to extreme mass ratio inspirals (EMRIs) in which the "particle" is a

black hole of small mass. Numerical relativity (NR) now gives us

answers about interactions of comparable mass black holes. The

comparison of PP and NR results, in principle, provides a mechanism

for studying some of the nonlinear effects when black holes interact.

Issues in the comparison, and important differences will be discussed.