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arXiv · 1211.3091

Nonanalyticity of the free energy in thermal field theory

F. T. Brandt·J. Frenkel·J. B. Siqueira
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Abstract

We study, in a d-dimensional space-time, the nonanalyticity of the thermal free energy in the scalar phi^4 theory as well as in QED. We find that the infrared divergent contributions induce, when d is even, a nonanalyticity in the coupling alpha of the form (alpha)^[(d-1)/2] whereas when d is odd the nonanalyticity is only logarithmic.

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F. T. Brandt, J. Frenkel, J. B. Siqueira. 2012-11-13. Nonanalyticity of the free energy in thermal field theory. https://doi.org/10.1103/physrevd.86.107701

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