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arXiv · 0912.4824

Transport Properties of QCD at Large $N_c$ and the Gauge/String Duality

Jorge Noronha
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Abstract

Below the deconfinement phase transition large $N_c$ QCD is expected to be a very viscous hadronic fluid because both the shear and bulk viscosity to entropy density ratio, $η/s,ζ/s \sim N_c^2$. In this letter I show that $η/s \sim N_c^2$ in the confined phase of holographic models of QCD at large $N_c$ defined in the supergravity approximation. Our results show that the gauge/string duality can be used to describe not only nearly perfect fluids but also extremely viscous systems such as a cold gas of glueballs.

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Jorge Noronha. 2010-03-06. Transport Properties of QCD at Large $N_c$ and the Gauge/String Duality. https://arxiv.org/abs/0912.4824

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