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arXiv · 2309.16328

Boundary terms in the Witten-Sakai-Sugimoto model at finite density

Lorenzo Bartolini·Sven Bjarke Gudnason
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Abstract

We consider the Witten-Sakai-Sugimoto model in the approximation of smeared instantons at finite density via a homogeneous Ansatz, which is known to be discontinuous in order to be able to contain a nonvanishing baryon density. The discontinuity at the infrared tip of the bulk spacetime gives rise to subtleties of discarding boundary terms that are normally discarded in the literature. We propose a reason for discarding this boundary term, by scrutinizing the currents and topological properties of the model. Along the way, we find a very effective and simple condition to compute the point of thermodynamic equilibrium.

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Lorenzo Bartolini, Sven Bjarke Gudnason. 2023-09-28. Boundary terms in the Witten-Sakai-Sugimoto model at finite density. https://doi.org/10.1103/physrevd.109.066006

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