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NJL and QCD from String Theory

E. Antonyan·J. A. Harvey·S. Jensen·D. Kutasov
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Abstract

We study a configuration of D-branes in string theory that is described at low energies by a four-dimensional field theory with a dynamically broken chiral symmetry. In a certain region of the parameter space of the brane configuration the low-energy theory is a non-local generalization of the Nambu-Jona-Lasinio (NJL) model. This vector model is exactly solvable at large N_c and dynamically breaks chiral symmetry at arbitrarily weak 't Hooft coupling. At strong coupling the dynamics is determined by the low-energy theory on D-branes living in the near-horizon geometry of other branes. In a different region of parameter space the brane construction gives rise to large N_c QCD. Thus the D-brane system interpolates between NJL and QCD.

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E. Antonyan, J. A. Harvey, S. Jensen, D. Kutasov. 2006-04-03. NJL and QCD from String Theory. https://arxiv.org/abs/hep-th/0604017

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