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arXiv · 1705.06403

Spontaneous symmetry breaking in replica field theory

R. Acosta Diaz·G. Menezes·N. F. Svaiter·C. A. D. Zarro
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Abstract

In this paper we discuss a disordered $d$-dimensional Euclidean $\lambda\varphi^{4}$ model. The dominant contribution to the average free energy of this system is written as a series of the replica partition functions of the model. In each replica partition function, using the saddle-point equations and imposing the replica symmetric ansatz, we show the presence of a spontaneous symmetry breaking mechanism in the disordered model. Moreover, the leading replica partition function must be described by a large-$N$ Euclidean replica field theory. We discuss finite temperature effects considering periodic boundary condition in Euclidean time and also using the Landau-Ginzburg approach. In the low temperature regime we prove the existence of $N$ instantons in the model.

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R. Acosta Diaz, G. Menezes, N. F. Svaiter, C. A. D. Zarro. 2017-05-18. Spontaneous symmetry breaking in replica field theory. https://doi.org/10.1103/physrevd.96.065012

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