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Renormalization-Group Theory and Universality along the Lambda Line of $^4$He

V. Dohm
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Abstract

The present status of the renormalization-group (RG) predictions on the superfluid density $ρ_s$ and the specific heat $C^+$ and $C^-$ near the $λ$-line of $^4He$ is briefly reviewed. Particular attention is given to universal amplitude ratios related to these quantities. The goals of a new theory project are presented that involves higher-order calculations of the amplitude functions of $ρ_s, C^+$ and $C^-$ which are of fundamental importance for a test of the universality predictions of the RG theory.

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V. Dohm. 1998-03-10. Renormalization-Group Theory and Universality along the Lambda Line of $^4$He. https://arxiv.org/abs/cond-mat/9803095

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