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arXiv · 0901.4942

Intersecting branes and Nambu$-$Jona-Lasinio model

Avinash Dhar·Partha Nag
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Abstract

We discuss chiral symmetry breaking in the intersecting brane model of Sakai and Sugimoto at weak coupling for a generic value of separation $L$ between the flavour $D8$ and anti-$D8$-branes. For any finite value of the radius $R$ of the circle around which the colour $D4$-branes wrap, a non-local Nambu$-$Jona-Lasinio (NJL) type short-range interaction couples the flavour branes and anti-branes. We argue that chiral symmetry is broken in this model only above a certain critical value of the 4-dimensional 't Hooft coupling and confirm this through numerical calculations of solutions to the gap equation. We also numerically investigate chiral symmetry breaking in the limit $R \to \infty$ keeping $L$ fixed, but find that simple ways of implementing this limit do not lead to a consistent picture of chiral symmetry breaking in the non-compact version of the non-local NJL model.

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Avinash Dhar, Partha Nag. 2009-03-16. Intersecting branes and Nambu$-$Jona-Lasinio model. https://doi.org/10.1103/physrevd.79.125013

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