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Finite Temperature Induced Fermion Number In The Nonlinear sigma Model In (2+1) Dimensions

Gerald V. Dunne·Justo Lopez-Sarrion·Kumar Rao
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Abstract

We compute the finite temperature induced fermion number for fermions coupled to a static nonlinear sigma model background in (2+1) dimensions, in the derivative expansion limit. While the zero temperature induced fermion number is well known to be topological (it is the winding number of the background), at finite temperature there is a temperature dependent correction that is nontopological -- this finite T correction is sensitive to the detailed shape of the background. At low temperature we resum the derivative expansion to all orders, and we consider explicit forms of the background as a CP^1 instanton or as a baby skyrmion.

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Gerald V. Dunne, Justo Lopez-Sarrion, Kumar Rao. 2002-04-09. Finite Temperature Induced Fermion Number In The Nonlinear sigma Model In (2+1) Dimensions. https://doi.org/10.1103/physrevd.66.025004

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