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arXiv · 2601.16743

The Pauli-Villars-regularised Dirac field coupled to electromagnetic fields at thermal equilibrium

William Borrelli·Umberto Morellini
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Abstract

In this paper we consider a model for the Dirac field in a classical electromagnetic field at thermal equilibrium. We adopt the Pauli-Villars regularisation technique in order to properly define the free energy of the equilibrium state, extending the previous work by the second named author on the purely magnetic case. This work provides a first step towards understanding polarisation effects in the Dirac field at thermal equilibrium, in the presence of both electrostatic and magnetic potentials.

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William Borrelli, Umberto Morellini. 2026-01-23. The Pauli-Villars-regularised Dirac field coupled to electromagnetic fields at thermal equilibrium. https://arxiv.org/abs/2601.16743

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