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arXiv · hep-th/9604192

Effective Critical Exponents from Finite Temperature Renormalization Group

Michael Strickland·Sen-Ben Liao
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Abstract

Effective critical exponents for the λϕ^4 scalar field theory are calculated as a function of the renormalization group block size k_o^{-1} and inverse critical temperature β_c. Exact renormalization group equations are presented up to first order in the derivative expansion and numerical solutions are obtained with and without polynomial expansion of the blocked potential. For a finite temperature system in d dimensions, it is shown that \barβ_c = β_c k_o determines whether the d-dimensional (\barβ_c << 1) or (d+1)-dimensional (\barβ_c >> 1) fixed point governs the phase transition. The validity of a polynomial expansion of the blocked potential near criticality is also addressed.

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Michael Strickland, Sen-Ben Liao. 1996-04-30. Effective Critical Exponents from Finite Temperature Renormalization Group. https://arxiv.org/abs/hep-th/9604192

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