Improved actions, the perfect action, and scaling by perturbation theory in Wilsons renormalization group: the two dimensional $O(N)$-invariant non linear $σ$-model in the hierarchical approximation

C. Wieczerkowski; Y. Xylander

doi:10.1016/0550-3213(95)00066-2

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arXiv · hep-th/9411191

Improved actions, the perfect action, and scaling by perturbation theory in Wilsons renormalization group: the two dimensional $O(N)$-invariant non linear $σ$-model in the hierarchical approximation

C. Wieczerkowski·Y. Xylander

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Abstract

We propose a method using perturbation theory in the running coupling constant and the idea of scaling to determine improved actions for lattice field theories combining Wilson's renormalization group with Symanzik's improvement program . The method is based on the analysis of a single renormalization group transformation. We test it on the hierarchical $O(N)$ invariant $σ$ model in two dimensions.

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C. Wieczerkowski, Y. Xylander. 1994-11-28. Improved actions, the perfect action, and scaling by perturbation theory in Wilsons renormalization group: the two dimensional $O(N)$-invariant non linear $σ$-model in the hierarchical approximation. https://doi.org/10.1016/0550-3213(95)00066-2

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