A nonlinear scalar model of extreme mass ratio inspirals in effective field theory II. Scalar perturbations and a master source

Abstract

The motion of a small compact object (SCO) in a background spacetime is investigated further in a class of model nonlinear scalar field theories having a perturbative structure analogous to the General Relativistic description of extreme mass ratio inspirals (EMRIs). We derive regular expressions for the scalar perturbations generated by the SCO's motion valid through third order in $\epsilon$, the size of the SCO to the background curvature length scale. Our expressions are compared to those calculated through second order in $\epsilon$ by Rosenthal in [E. Rosenthal, CQG 22, S859 (2005)] and found to agree but our procedure for regularizing the scalar perturbations is considerably simpler. Following the Detweiler-Whiting (DW) scheme, we use our regular expressions for the field and derive the regular self-force corrections through third order. We find agreement with our previous derivation based on a variational principle of an effective action for the worldline associated with the SCO thus demonstrating the internal consistency of our formalism. This also explicitly demonstrates that the DW decomposition of Green's functions is a valid and practical method of self force computation at higher orders in perturbation theory and, as we show in an appendix, at all orders in perturbation theory. Finally, we identify a master source from which all other physically relevant quantities are derivable. Knowing the master source perturbatively allows one to construct the waveform measured by an observer, the regular part of the field on the worldline, the regular part of the self force, and orbital quantities such as shifts of the innermost stable circular orbit, etc. The existence of a master source together with the regularization methods implemented in this series should be indispensable for derivations of higher-order gravitational self force corrections.

For Part 1 of this series, see arXiv:1012.4488. 20 pages, 7 figures

References in corpus (4)

• Two timescale analysis of extreme mass ratio inspirals in Kerr. I. Orbital Motion
• Self-force on extreme mass ratio inspirals via curved spacetime effective field theory
• Construction of the second-order gravitational perturbations produced by a compact object
• A nonlinear scalar model of extreme mass ratio inspirals in effective field theory I. Self force through third order

Cited by in corpus (16)

• The Effective Field Theorist's Approach to Gravitational Dynamics
• Self-force and radiation reaction in general relativity
• Effective Field Theories of Post-Newtonian Gravity: A comprehensive review
• Binary dynamics from spin1-spin2 coupling at fourth post-Newtonian order
• Tail terms in gravitational radiation reaction via effective field theory
• Nonlinear gravitational self-force. I. Field outside a small body
• Self-force via $m$-mode regularization and 2+1D evolution: III. Gravitational field on Schwarzschild spacetime
• High-order expansions of the Detweiler-Whiting singular field in Schwarzschild spacetime
• Motion of small objects in curved spacetimes: An introduction to gravitational self-force
• Self-force via Green functions and worldline integration
• Gravitational self-force in the ultra-relativistic limit: The 'large-N' expansion
• Self-force: Computational Strategies
• A nonlinear scalar model of extreme mass ratio inspirals in effective field theory I. Self force through third order
• Radiation-Reaction Force on a Small Charged Body to Second Order
• Gravitational self-force in non-vacuum spacetimes: an effective field theory derivation
• Regularization of a scalar charged particle for generic orbits in Kerr spacetime