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Transport Coefficients and Analytic Continuation in Dual 1+1 Dimensional Models at Finite Temperature

T. S. Evans·A. Gomez Nicola·R. J. Rivers·D. A. Steer
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Abstract

The conductivity of a finite temperature 1+1 dimensional fermion gas described by the massive Thirring model is shown to be related to the retarded propagator of the dual boson sine-Gordon model. Duality provides a natural resummation which resolves infra-red problems, and the boson propagator can be related to the fermion gas at non-zero temperature and chemical potential or density. In addition, at high temperatures, we can apply a dimensional reduction technique to find resummed closed expressions for the boson self-energy and relate them to the fermion conductivity. Particular attention is paid to the discussion of analytic continuation. The resummation implicit in duality provides a powerful alternative to the standard diagrammatic evaluation of transport coefficients at finite temperature.

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T. S. Evans, A. Gomez Nicola, R. J. Rivers, D. A. Steer. 2002-04-19. Transport Coefficients and Analytic Continuation in Dual 1+1 Dimensional Models at Finite Temperature. https://doi.org/10.1016/s0550-3213(02)01145-8

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