Fractionized Skyrmions in Dense Compact-Star Matter

Abstract

The hadronic matter described as a skyrmion matter embedded in an FCC crystal is found to turn into a half-skyrmion matter with vanishing (in the chiral limit) quark condensate and {\it non-vanishing} pion decay constant {$f_{\pi }$} at a density $n_{1/2}$ lower than or near the critical density $n_c$ at which hadronic matter changes over to a chiral symmetry restored phase with possibly deconfined quarks. When hidden local gauge fields and a dilaton scalar of spontaneously broken scale symmetry with decay constant $f_{\chi }$ are incorporated, this half-skyrmion phase is characterized by $f_{\chi }\approx f_{\pi }\ne 0$ with the hidden gauge coupling $g\ne 0$ but $\ll 1$. While chiral symmetry is restored {\it globally} in this region in the sense that space-averaged, $\la\bar{q}q\ra$ vanishes, quarks are still confined in massive hadrons and massless pions. This phase is shown to play a crucial role in the model for a smooth transition from a soft EoS at low density to a stiffer EoS at high density, the changeover taking place at $n_{1/2}\sim 2n_0$. It resembles the "quarkyonic phase" predicted in large $N_c$ QCD and represents the "hadronic freedom" regime which figures as a doorway to chiral restoration. The fractionization of skyrmion matter into half-skyrmion matter has a tantalizing analogy to what appears to happen in condensed matter in (2+1) dimensions where half-skyrmions or "merons" enter as relevant degrees of freedom at the interface.

To appear in {\it The Multifaceted Skyrmion} (2nd Edition) (World Scientific, Singapore) ed. by M. Rho and I. Zahed; typos corrected

References in corpus (13)

• Light scalar at LHC: the Higgs or the dilaton?
• QCD and dimensional deconstruction
• Chiral three-nucleon interaction and the carbon-14 dating beta decay
• Nucleons and parity doubling across the deconfinement transition
• Half-Skyrmions, Tensor Forces and Symmetry Energy in Cold Dense Matter
• Scale-Invariant Hidden Local Symmetry, Topology Change and Dense Baryonic Matter II
• Symmetries of hadrons after unbreaking the chiral symmetry
• Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions
• Symmetry energy systematics and its high density behavior
• Implications of Holographic QCD in ChPT with Hidden Local Symmetry
• Inhomogeneous quark condensate in compressed skyrmion matter
• Old Wine in a New Bottle: Technidilaton as the 125 GeV Higgs -- Dedicated to the late Professor Yoichiro Nambu
• Density-dependent nuclear interactions and the beta decay of 14C: chiral three-nucleon forces and Brown-Rho scaling

Cited by in corpus (3)

• Mapping topology to nuclear dilaton-HLS effective field theory for dense baryonic matter
• Probing the Source of Proton Mass by"Unbreaking" Scale-Chiral Symmetry
• Mapping topology of skyrmions and fractional quantum Hall droplets to nuclear EFT for ultra-dense baryonic matter