Scalar Self-force for High Spin Black Holes

Understand

We semianalytically investigate the scalar self-force experienced in the final stages of extreme mass ratio inspirals of nonspinning scalar particles into supermassive nearly extremal Kerr black holes.

• We exploit the near-horizon conformal symmetry to find the self-force for general corotating equatorial geodesics.
• The angular component of the self-force is shown to be universal at leading order in the high spin limit.
• We verify that the energy and angular momentum losses of the scalar particle match with the asymptotic fluxes of scalar radiation.