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Thermal Bosonic and Fermionic Quantum Fields in Static Background Gauge Potentials

A. A. Actor·K. D. Rothe·F. G. Scholtz
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Abstract

We study at finite temperature the energy-momentum tensor $T_{μν}(x)$ of (i) a scalar field in arbitrary dimension, and (ii) a spinor field in 1+1 dimensions, interacting with a static background electromagnetic field. $T_{μν}$ separates into an UV divergent part $T_{μν}^{sea}$ representing the virtual sea, and an UV finite part $T_{μν}^{plasma}$ describing the thermal plasma of the matter field. $T_{μν}^{sea}$ remains uniform in the presence of a \underbar{uniform} electric field $\vec E$, while $T_{μν}^{plasma}$ becomes a periodic function with period $Δx=2πT/E$ in the direction parallel to $\vec E$. A related periodicity is found for a uniform static magnetic field if one spatial direction perpendicular to the magnetic field is compactified to a circle.

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A. A. Actor, K. D. Rothe, F. G. Scholtz. 1998-09-04. Thermal Bosonic and Fermionic Quantum Fields in Static Background Gauge Potentials. https://doi.org/10.1103/physrevd.60.105034

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