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arXiv · hep-th/0207230

Finite temperature regularization

C. D. Fosco·F. A. Schaposnik
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Abstract

We present a non-perturbative regularization scheme for Quantum Field Theories which amounts to an embedding of the originally unregularized theory into a spacetime with an extra compactified dimensions of length L ~ Lambda^{-1} (with Lambda an ultraviolet cutoff), plus a doubling in the number of fields, which satisfy different periodicity conditions and have opposite Grassmann parity. The resulting regularized action may be interpreted, for the fermionic case, as corresponding to a finite-temperature theory with a supersymmetry, which is broken because of the boundary conditions. We test our proposal in a perturbative calculation (the vacuum polarization graph for a D-dimensional fermionic theory) and in a non-perturbative one (the chiral anomaly).

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C. D. Fosco, F. A. Schaposnik. 2002-07-25. Finite temperature regularization. https://doi.org/10.1016/s0370-2693(02)02735-1

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