A photon density wavefunction

Stéphane Virally

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arXiv · 2507.16597

A photon density wavefunction

Stéphane Virally

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Abstract

Maxwell's equations in the vacuum can be formally cast in the form of Schr\"odinger's equation. Unfortunately, the vector to which this equation directly applies is not a wavefunction: its amplitude squared is not a probability density but the expected energy density of the field. Since we can count photons, there must be a more convincing wavefunction, derived from the EM field, whose amplitude squared is an expected photon density. Mandel proposed the second quantized version of such a wavefunction, but did not link it directly to the EM field. We show how this can be accomplished.

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BibTeX RIS

Stéphane Virally. 2025-07-22. A photon density wavefunction. https://arxiv.org/abs/2507.16597

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