A Perturbative Improvement of the Hierarchical Approximation

Yannick Meurice

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arXiv · hep-th/9307128

A Perturbative Improvement of the Hierarchical Approximation

Yannick Meurice

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Abstract

We propose a perturbative improvement of the hierarchical approximation for gaussian models. The procedure is based on a relabeling of the momenta which allows one to express the symmetries of the hierarchical model using a simple multiplication group. The representations of this group are used to expand the action. The perturbative expansion is treated as a problem of symmetry breaking using Ward identity techniques.

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Yannick Meurice. 1993-07-20. A Perturbative Improvement of the Hierarchical Approximation. https://arxiv.org/abs/hep-th/9307128

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