Universal effective action for O(n)-symmetric λϕ^4 model from renormalization group

A. I. Sokolov; E. V. Orlov; V. A. Ul'kov; S. S. Kashtanov

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arXiv · hep-th/9808011

Universal effective action for O(n)-symmetric λϕ^4 model from renormalization group

A. I. Sokolov·E. V. Orlov·V. A. Ul'kov·S. S. Kashtanov

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Abstract

The RG expansions for renormalized coupling constants g_6 and g_8 of the 3D n-vector model are calculated in the 4-loop and 3-loop approximations respectively. Resummation of the RG series for g_6 by the Pade-Borel-Leroy technique results in the estimates for its universal critical values g_6^*(n) which are argued to deviate from the exact numbers by less than 0.3%. The RG expansion for g_8 demonstrates stronger divergence being much less suitable for getting reliable numerical estimates.

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A. I. Sokolov, E. V. Orlov, V. A. Ul'kov, S. S. Kashtanov. 1998-08-04. Universal effective action for O(n)-symmetric λϕ^4 model from renormalization group. https://arxiv.org/abs/hep-th/9808011

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