Inhomogeneous chiral symmetry breaking in dense neutron-star matter

Abstract

An increasing number of model results suggests that chiral symmetry is broken inhomogeneously in a certain window at intermediate densities in the QCD phase diagram. This could have significant effects on the properties of compact stars, possibly leading to new astrophysical signatures. In this contribution we discuss this idea by reviewing recent results on inhomogeneous chiral symmetry breaking under an astrophysics-oriented perspective. After introducing two commonly studied spatial modulations of the chiral condensate, the chiral density wave and the real kink crystal, we focus on their properties and their effect on the equation of state of quark matter. We also describe how these crystalline phases are affected by different elements which are required for a realistic description of a compact star, such as charge neutrality, the presence of magnetic fields, vector interactions and the interplay with color-superconductivity. Finally, we discuss possible signatures of inhomogeneous chiral symmetry breaking in the core of compact stars, considering the cases of mass-radius relations and neutrino emissivity explicitly.

Invited contribution to the EPJA Topical Issue "Exotic Matter in Neutron Stars". v2: extended discussion on strange quarks, updated mass-radius section, other small changes; matches published version. 16 pages, 14 figures

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Cited by in corpus (25)

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• Fluctuations in cool quark matter and the phase diagram of Quantum Chromodynamics
• The Lifshitz Regime and its Experimental Signals
• Crystalline phases by an improved gradient expansion technique
• Influence of vector interactions on the favored shape of inhomogeneous chiral condensates
• A novel Dual Chiral Density Wave in nuclear matter based on a parity doublet structure
• Quark matter contribution to the heat capacity of magnetized neutron stars
• Compact objects in and beyond the Standard Model from non-perturbative vacuum scalarization
• Magnetic catalysis in the (2+1)-dimensional Gross-Neveu model
• Chiral density wave versus pion condensation in the 1+1 dimensional NJL model
• Consistent regularization and renormalization in models with inhomogeneous phases
• The magnetized (2+1)-dimensional Gross-Neveu model at finite density
• Magnetic fields in turbulent quark matter and magnetar bursts
• Dilepton production from moaton quasiparticles
• Constraining gravity with hadron physics: neutron stars, modified gravity and gravitational waves
• Axion-Polaritons in quark stars: a possible solution to the missing pulsar problem
• Time-dependent Ginzburg-Landau approach to the dynamics of inhomogeneous chiral condensates in a nonlocal Nambu--Jona-Lasinio model
• Magnetic field effect on nuclear matter from skyrmion crystal model
• Gradient expansion technique for inhomogeneous, magnetized quark matter
• Magnetic field instability driven by anomalous magnetic moments of massive fermions and electroweak interaction with background matter
• Thermodynamic potential for quark-gluon plasma with finite quark masses and chemical potential
• Bulk Viscosity of Two-Flavor Color Superconducting Quark Matter in Neutron Star Mergers
• Low energy physics of interacting bosons with a moat spectrum, and the implications for condensed matter and cold nuclear matter
• Color-superconductivity and inhomogeneous chiral symmetry breaking in isospin-asymmetric quark matter
• New magnetic field instability and magnetar bursts