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Is the number of Photons a Classical Invariant?

J. E. Avron·E. Berg·D. Goldsmith·A. Gordon
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Abstract

We describe an apparent puzzle in classical electrodynamics and its resolution. It is concerned with the Lorentz invariance of the classical analog of the number of photons.

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J. E. Avron, E. Berg, D. Goldsmith, A. Gordon. 1999-04-20. Is the number of Photons a Classical Invariant?. https://doi.org/10.1088/0143-0807%2F20%2F3%2F304

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