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arXiv · 1007.2494

Holographic chiral currents in a magnetic field

Anton Rebhan·Andreas Schmitt·Stefan Stricker
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Abstract

In the presence of a quark chemical potential, a magnetic field induces an axial current in the direction of the magnetic field. We compute this current in the Sakai-Sugimoto model, a holographic model which, in a certain limit, is dual to large-N_c QCD. We also compute the analogous vector current, for which an axial chemical potential is formally introduced. This vector current can potentially be observed via charge separation in heavy-ion collisions. After implementing the correct axial anomaly in the Sakai-Sugimoto model we find an axial current in accordance with previous studies and a vanishing vector current, in apparent contrast to previous weak-coupling calculations.

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Anton Rebhan, Andreas Schmitt, Stefan Stricker. 2010-07-15. Holographic chiral currents in a magnetic field. https://doi.org/10.1143/ptps.186.463

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