Regularization of a scalar charged particle for generic orbits in Kerr spacetime
Abstract
A scalar charged particle moving in a curved background spacetime will emit a field affecting its own motion; the resolving of this resulting motion is often referred to as the selfforce problem. This also serves as a toy model for the astrophysically interesting compactbody binaries, extreme mass ratio inspirals, targets for the future spacebased gravitational wave detector, LISA. In the modeling of such systems, a pointparticle assumption leads to problematic singularities which need to be safely removed to solve for the motion of the particle regardless of the scenario; scalar, electromagnetic, or gravitational. Here, we concentrate on a scalar charged particle and calculate the next order of the DetweilerWhiting singular field and its resulting regularization parameter when employing the modesum method of regularization. This enables sufficiently faster selfforce calculations giving the same level of accuracy with significantly less ℓ modes. Due to the similarity of the governing equations, this also lays the groundwork for similar calculations for an electromagnetic or mass charged particle in Kerr spacetime and has applications in other regularization schemes like the effective source and matched expansion.
 Publication:

Physical Review D
 Pub Date:
 September 2022
 DOI:
 10.1103/PhysRevD.106.064031
 arXiv:
 arXiv:2107.14750
 Bibcode:
 2022PhRvD.106f4031H
 Keywords:

 General Relativity and Quantum Cosmology;
 Astrophysics  High Energy Astrophysical Phenomena;
 High Energy Physics  Theory
 EPrint:
 25 pages, updated with published version, accepted by Phys. Rev. D on July 7, 2022, published Sept 15, 2022