Holographic QCD in the Veneziano limit and neutron stars

TL;DR

This paper employs holographic V-QCD models to predict the equation of state for dense quark matter, aligning with neutron star observations and analyzing phase transitions between baryonic and quark matter.

Contribution

It introduces a holographic approach to dense QCD, matching lattice results and astrophysical constraints to study neutron star matter and phase transitions.

Findings

Pressure in V-QCD aligns with neutron star matter EoS.

Baryon density at phase transition is at least 2.9 times nuclear saturation density.

Phase transition is strongly first order at densities below 7.5 times nuclear saturation density.

Abstract

We use the holographic V-QCD models to analyse the physics of dense QCD and neutron stars. Accommodating lattice results for thermodynamics of QCD enables us to make generic predictions for the Equation of State (EoS) of the quark matter phase in the cold and dense regime. We demonstrate that the resulting pressure in V-QCD matches well with a family of neutron-star-matter EoSs that interpolate between state-of-the-art theoretical results for low and high density QCD. After implementing the astrophysical constraints, i.e., the largest known neutron star mass and the recent LIGO/Virgo results for the tidal deformability, we analyse the phase transition between the baryonic and quark matter phases. We find that the baryon density $n_B$ at the transition is at least 2.9 times the nuclear saturation density $n_s$. The transition is of strongly first order at low and intermediate densities, i.e., for $n_B/n_s \lesssim 7.5$.