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arXiv · 1911.12705

Deconfined, Massive Quark Phase at High Density and Compact Stars: A Holographic Study

Abstract

In Hoyos et al. (arXiv:1603.02943) a holographic D3/D7 system was used to describe a deconfined yet massive quark phase of QCD at finite density, concluding that the equation of state of such a phase was not stiff enough to support exotic dense stars. That analysis used a hard quark mass to represent the dynamical mass and assumed a conformal gauge background. Here we phenomenologically adjust the D3/D7 system to include a running anomalous dimension for the quark condensate. This introduces a dynamical mechanism for chiral symmetry breaking yet the model still has a deconfined massive phase at intermediate densities. We show that these systems, dependent on the running profile in the deep IR, generate much stiffer equations of state and non-monotonic behaviour in the speed of sound. The results suggest that these equations of state may be closer to supporting hybrid stars with quark cores.

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Kazem Bitaghsir Fadafan, Jesus Cruz Rojas, Nick Evans. 2020-06-04. Deconfined, Massive Quark Phase at High Density and Compact Stars: A Holographic Study. https://doi.org/10.1103/physrevd.101.126005

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