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arXiv · hep-th/0405264

Finite Temperature Quantum Field Theory with Impurities

M. Mintchev·P. Sorba
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Abstract

We apply the concept of reflection-transmission (RT) algebra, originally developed in the context of integrable systems in 1+1 space-time dimensions, to the study of finite temperature quantum field theory with impurities in higher dimensions. We consider a scalar field in $(s+1)+1$ space-time dimensions, interacting with impurities localized on $s$-dimensional hyperplanes, but without self-interaction. We discuss first the case $s=0$ and extend afterwards all results to $s>0$. Constructing the Gibbs state over an appropriate RT algebra, we derive the energy density at finite temperature and establish the correction to the Stefan-Boltzmann law generated by the impurity. The contribution of the impurity bound states is taken into account. The charge density profiles for various impurities are also investigated.

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BibTeXRIS

M. Mintchev, P. Sorba. 2004-06-11. Finite Temperature Quantum Field Theory with Impurities. https://doi.org/10.1088/1742-5468%2F2004%2F07%2Fp07001

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