Accuracy of the Post-Newtonian Approximation for Extreme-Mass Ratio Inspirals from Black-hole Perturbation Approach

摘要

We revisit the accuracy of the post-Newtonian (PN) approximation and itsregion of validity for quasi-circular orbits of a point particle in the Kerrspacetime, by using an analytically known highest post-Newtonian ordergravitational energy flux and accurate numerical results in the black holeperturbation approach. It is found that regions of validity become larger forhigher PN order results although there are several local maximums in regions ofvalidity for relatively low-PN order results. This might imply that higher PNorder calculations are also encouraged for comparable-mass binaries.