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On stability of the three-dimensional fixed point in a model with three coupling constants from the $ε$ expansion: Three-loop results

Andrei Mudrov·Konstantin Varnashev
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Abstract

The structure of the renormalization-group flows in a model with three quartic coupling constants is studied within the $ε$-expansion method up to three-loop order. Twofold degeneracy of the eigenvalue exponents for the three-dimensionally stable fixed point is observed and the possibility for powers in $\sqrtε$ to appear in the series is investigated. Reliability and effectiveness of the $ε$-expansion method for the given model is discussed.

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Andrei Mudrov, Konstantin Varnashev. 1998-02-05. On stability of the three-dimensional fixed point in a model with three coupling constants from the $ε$ expansion: Three-loop results. https://doi.org/10.1103/physrevb.57.5704

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