On the Nature of the Gaussian Approximations in Phase Ordering Kinetics s

De Siena; M. Zannetti

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On the Nature of the Gaussian Approximations in Phase Ordering Kinetics s

De Siena·M. Zannetti

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Abstract

The structure of the gaussian auxiliary field approximation in the theory of phase ordering kinetics is analysed with the aim of placing the method within the context of a systematic theory. While we are unable to do this for systems with a scalar order parameter, where the approximation remains uncontrolled, a systematic development about the gaussian approximation can be outlined for systems with a vector order parameter in terms of a suitably defined $1/N$-expansion.

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De Siena, M. Zannetti. 1994-09-09. On the Nature of the Gaussian Approximations in Phase Ordering Kinetics s. https://arxiv.org/abs/cond-mat/9409040

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