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arXiv · 0807.1150

Self-forces from generalized Killing fields

Abraham I. Harte
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Abstract

A non-perturbative formalism is developed that simplifies the understanding of self-forces and self-torques acting on extended scalar charges in curved spacetimes. Laws of motion are locally derived using momenta generated by a set of generalized Killing fields. Self-interactions that may be interpreted as arising from the details of a body's internal structure are shown to have very simple geometric and physical interpretations. Certain modifications to the usual definition for a center-of-mass are identified that significantly simplify the motions of charges with strong self-fields. A derivation is also provided for a generalized form of the Detweiler-Whiting axiom that pointlike charges should react only to the so-called regular component of their self-field. Standard results are shown to be recovered for sufficiently small charge distributions.

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Abraham I. Harte. 2008-07-08. Self-forces from generalized Killing fields. https://doi.org/10.1088/0264-9381%2F25%2F23%2F235020

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