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arXiv:2208.13991 · Physical review. D/Physical review. D.

Tensor renormalization group approach to ( 1+1 )-dimensional SU(2) principal chiral model at finite density

Xiao Luo, Y. Kuramashi

Published May 19, 2023• 10 citations
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Abstract

We apply the tensor renormalization group method to the ($1+1$)-dimensional SU(2) principal chiral model at finite chemical potential with the use of the Gauss-Legendre quadrature to discretize the SU(2) Lie group. The internal energy at vanishing chemical potential $\ensuremath{\mu}=0$ shows good consistency with the prediction of the strong and weak coupling expansions. This indicates an effectiveness of the Gauss-Legendre quadrature for the partitioning of the SU(2) Lie group. In the finite density region with $\ensuremath{\mu}\ensuremath{\ne}0$ at the strong coupling we observe the Silver-Blaze phenomenon for the number density.

DOI
10.1103/physrevd.107.094509

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