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arXiv · 1110.2037

Asymptotic Freedom in Holographic QCD

Abstract

We calculate the running of the quark mass and the quark condensate using a dynamical soft-wall model by Csaki and Reece. We show that a correct running can be obtained with an appropriate sign for the dilaton field. In the soft-wall model with quadratic dilaton profile, a wrong sign for the dilaton field can give rise to a massless vector meson, a signature of spontaneously broken symmetry in the vector sector, which is not observed in nature. With a right parameter range, we obtain no such massless vector meson. We also find that, contrary to the soft-wall model with quadratic dilaton profile, the model allows a non-vanishing quark condensate in the chiral limit. We obtain the vector meson mass spectrum similar to that of the hard-wall model. By varying a parameter in the model we can fit the running of the quark mass and of the quark condensate.

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BibTeXRIS

Zainul Abidin, Herry J. Kwee, Jong Anly Tan. 2011-10-11. Asymptotic Freedom in Holographic QCD. https://doi.org/10.1007/jhep12(2011)026

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