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arXiv · 1103.3551

Scalar Quantum Field Theory in Disordered Media

E. Arias·E. Goulart·G. Krein·G. Menezes·N. F. Svaiter
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Abstract

A free massive scalar field in inhomogeneous random media is investigated. The coefficients of the Klein-Gordon equation are taken to be random functions of the spatial coordinates. The case of an annealed-like disordered medium, modeled by centered stationary and Gaussian processes, is analyzed. After performing the averages over the random functions, we obtain the two-point causal Green's function of the model up to one-loop. The disordered scalar quantum field theory becomes qualitatively similar to a $λϕ^{4}$ self-interacting theory with a frequency-dependent coupling.

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E. Arias, E. Goulart, G. Krein, G. Menezes, N. F. Svaiter. 2011-03-18. Scalar Quantum Field Theory in Disordered Media. https://doi.org/10.1103/physrevd.83.125022

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