Critical exponents of the O(N) model in the infrared limit from functional renormalization

S. Nagy

doi:10.1103/physrevd.86.085020

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arXiv · 1201.1625

Critical exponents of the O(N) model in the infrared limit from functional renormalization

S. Nagy

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Abstract

We determined the critical exponent $ν$ of the scalar O(N) model with a strategy based on the definition of the correlation length in the infrared limit. The functional renormalization group treatment of the model shows that there is an infrared fixed point in the broken phase. The appearing degeneracy induces a dynamical length scale there, which can be considered as the correlation length. It is shown that the IR scaling behavior can account either for the Ising type phase transition in the 3-dimensional O(N) model, or for the Kosterlitz-Thouless type scaling of the 2-dimensional O(2) model.

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S. Nagy. 2012-09-12. Critical exponents of the O(N) model in the infrared limit from functional renormalization. https://doi.org/10.1103/physrevd.86.085020

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