Scale-Invariant Hidden Local Symmetry, Topology Change and Dense Baryonic Matter

TL;DR

This paper develops a scale-invariant hidden local symmetry model incorporating topology change to describe dense baryonic matter, successfully predicting the equation of state for compact stars consistent with observational data.

Contribution

It introduces a novel scale-invariant HLS framework with density-dependent parameters, linking topology change to dense matter properties and stellar observations.

Findings

Successfully predicts the EoS of dense matter in compact stars.

Reproduces properties of normal nuclear matter.

Provides insights into symmetry manifestations in compressed baryonic matter.

Abstract

When scale symmetry is implemented into hidden local symmetry in low-energy strong interactions to arrive at a scale-invariant hidden local symmetric (HLS) theory, the scalar $f_0(500)$ may be interpreted as pseudo-Nambu-Goldstone (pNG) boson, i.e., dilaton, of spontaneously broken scale invariance, joining the pseudo-scalar pNG bosons $\pi$ and the matter fields $V=(\rho,\omega)$ as relevant degrees of freedom. Implementing the skyrmion-half-skyrmion transition predicted at large $N_c$ in QCD at a density roughly twice the nuclear matter density found in the crystal simulation of dense skyrmion matter, we determine the intrinsically density-dependent (IDD) "bare parameters" of the scale-invariant HLS Lagrangian matched to QCD at a matching scale $\Lambda_M$. The resulting effective Lagrangian, with the parameters scaling with the density of the system, is applied to nuclear matter and dense baryonic matter relevant to massive compact stars by means of the double-decimation renormalization-group $V_{lowk}$ formalism. We satisfactorily post-dict the properties of normal nuclear matter and more significantly {\it predict} the EoS of dense compact-star matter that quantitatively accounts for the presently available data coming from both the terrestrial and space laboratories. We interpret the resulting structure of compact-star matter as revealing how the combination of hidden-scale symmetry and hidden local symmetry manifests itself in compressed baryonic matter.