Wilsonian renormalization group approach to the lower dimensional nonlinear sigma models

Kiyoshi Higashijima; Etsuko Itou

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arXiv · hep-th/0511300

Wilsonian renormalization group approach to the lower dimensional nonlinear sigma models

Kiyoshi Higashijima·Etsuko Itou

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Abstract

In this paper, we study three dimensional NL$σ$Ms within two kind of nonperturbative methods; WRG and large-N expansion. First, we investigate the renormalizability of some NL$σ$Ms using WRG equation. We find that some models have a nontrivial UV fixed point and are renormalizable within nonperturbative method. Second, we study the phase structure of $CP^{N-1}$ and $Q^{N-2}$ models using large-N expansion. These two models have two and three phases respectively. At last, we construct the conformal field theories at the fixed point of the nonperturbative WRG $β$ function. This is the review of recently works and is based on the talk of the conference by EI.

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Kiyoshi Higashijima, Etsuko Itou. 2005-11-30. Wilsonian renormalization group approach to the lower dimensional nonlinear sigma models. https://arxiv.org/abs/hep-th/0511300

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