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Two-loop Critical Fluctuation-Dissipation Ratio for the Relaxational Dynamics of the O(N) Landau-Ginzburg Hamiltonian

Pasquale Calabrese·Andrea Gambassi
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Abstract

The off-equilibrium purely dissipative dynamics (Model A) of the O(N) vector model is considered at criticality in an $ε= 4- d > 0$ up to O($ε^2$). The scaling behavior of two-time response and correlation functions at zero momentum, the associated universal scaling functions, and the nontrivial limit of the fluctuation-dissipation ratio are determined in the aging regime.

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Pasquale Calabrese, Andrea Gambassi. 2002-09-30. Two-loop Critical Fluctuation-Dissipation Ratio for the Relaxational Dynamics of the O(N) Landau-Ginzburg Hamiltonian. https://doi.org/10.1103/physreve.66.066101

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