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arXiv · 1707.04222

The Motion of Small Bodies in Space-time

Robert Geroch·James Owen Weatherall
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Abstract

We consider the motion of small bodies in general relativity. The key result captures a sense in which such bodies follow timelike geodesics (or, in the case of charged bodies, Lorentz-force curves). This result clarifies the relationship between approaches that model such bodies as distributions supported on a curve, and those that employ smooth fields supported in small neighborhoods of a curve. This result also applies to "bodies" constructed from wave packets of Maxwell or Klein-Gordon fields. There follows a simple and precise formulation of the optical limit for Maxwell fields.

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Robert Geroch, James Owen Weatherall. 2017-07-13. The Motion of Small Bodies in Space-time. https://doi.org/10.1007/s00220-018-3268-8

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