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arXiv · 1504.00749

The RG flow of Nambu--Jona-Lasinio model at finite temperature and density

Ken-Ichi Aoki·Masatoshi Yamada
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Abstract

We study the Nambu--Jona-Lasinio model at finite temperature and finite density by using the functional renormalization group. The RG flows of the four-fermi coupling constant in the NJL model are investigated. We obtain the chiral phase boundary in cases of the large-$N$ leading approximation and an improved approximation. The large-$N$ non-leading term at the vanishing temperature has a singularity at the fermi surface. We show that the quantum corrections by the large-$N$ non-leading term largely influence the phase boundary at the low temperature and high density region.

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Ken-Ichi Aoki, Masatoshi Yamada. 2015-04-03. The RG flow of Nambu--Jona-Lasinio model at finite temperature and density. https://doi.org/10.1142/s0217751x15501808

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