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arXiv · 2606.26946

On the simple derivation of the Casimir effect

Hai-Chau Nguyen·Matthias Kleinmann
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Abstract

The Casimir effect in its simplest form describes the attraction of two parallel conducting plates at close distance due to the vacuum fluctuation of the electromagnetic field. Its derivation can be found in many introductory works on quantum optics. Here we return to the original paper by Casimir and find subtle nuances in his derivation that are worth discussing to give a complete picture of a mathematically sound derivation of the effect.

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Hai-Chau Nguyen, Matthias Kleinmann. 2026-06-25. On the simple derivation of the Casimir effect. https://arxiv.org/abs/2606.26946

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