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arXiv · hep-th/0605138

NGN, QCD_2 and chiral phase transition from string theory

Yi-hong Gao·Weishui Xu·Ding-fang Zeng
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Abstract

We construct a D2-D8-$\bar{D8}$ configuration in string theory, it can be described at low energy by two dimensional field theory. In the weak coupling region, the low energy theory is a nonlocal generalization of Gross-Neveu(GN) model which dynamically breaks the chiral flavor symmetry $U(N_f)_L \times U(N_f)_R$ at large $N_c$ and finite $N_f$. However, in the strong coupling region, we can use the SUGRA/Born-Infeld approximation to describe the low energy dynamics of the system. Also, we analyze the low energy dynamics about the configuration of wrapping the one direction of D2 brane on a circle with anti-periodic boundary condition of fermions. The fermions and scalars on D2 branes get mass and decouple from the low energy theory. The IR dynamics is described by the $QCD_2$ at weak coupling. In the opposite region, the dynamics has a holographic dual description. And we have discussed the phase transition of chiral symmetry breaking at finite temperature. Finally, after performing T-duality, this configuration is related to some other brane configurations.

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Yi-hong Gao, Weishui Xu, Ding-fang Zeng. 2006-09-01. NGN, QCD_2 and chiral phase transition from string theory. https://doi.org/10.1088/1126-6708%2F2006%2F08%2F018

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