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An introduction to the Lorentz-Dirac equation

Eric Poisson
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Abstract

These notes provide two derivations of the Lorentz-Dirac equation. The first is patterned after Landau and Lifshitz and is based on the observation that the half-retarded minus half-advanced potential is entirely responsible for the radiation-reaction force. The second is patterned after Dirac, and is based upon considerations of energy-momentum conservation; it relies exclusively on the retarded potential. The notes conclude with a discussion of the difficulties associated with the interpretation of the Lorentz-Dirac equation as an equation of motion for a point charge. The presentation is essentially self-contained, but the reader is assumed to possess some elements of differential geometry (necessary for the second derivation only).

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Eric Poisson. 1999-12-10. An introduction to the Lorentz-Dirac equation. https://arxiv.org/abs/gr-qc/9912045

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