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On the Perturbation Expansion of the KPZ-Equation

Kay Joerg Wiese
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Abstract

We present a simple argument to show that the beta-function of the d-dimensional KPZ-equation (d>=2) is to all orders in perturbation theory given by beta(g) = (d-2) g - 2/(8 pi)^(d/2) Gamma(2-d/2) g^2 . Neither the dynamical exponent z nor the roughness-exponent zeta have any correction in any order of perturbation theory. This shows that standard perturbation theory cannot attain the strong-coupling regime and in addition breaks down at d=4. We also calculate a class of correlation-functions exactly.

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BibTeXRIS

Kay Joerg Wiese. 1998-07-06. On the Perturbation Expansion of the KPZ-Equation. https://doi.org/10.1023/b%3Ajoss.0000026730.76868.c4

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