Manifestation of hidden symmetries in baryonic matter: From finite nuclei to neutron stars
Abstract
When hadron-quark continuity is formulated in terms of a topology change at a density higher than twice the nuclear matter density (n0)(n0), the core of massive compact stars can be described in terms of quasiparticles of fractional baryon charges, behaving neither like pure baryons nor like deconfined quarks. Hidden symmetries, both local gauge and pseudo-conformal (or broken scale), emerge and give rise both to the long-standing “effective g∗A≈1g∗A≈1” in nuclear Gamow–Teller (GT) transitions at ≲n0 and to the pseudo-conformal sound velocity v2pcs/c2≈1/3 at ≳3n0. It is suggested that what has been referred to, since a long time, as “quenched gA” in light nuclei reflects what leads to the dilaton-limit gDLA=1 at near the (putative) infrared fixed point of scale invariance. These properties are confronted with the recent observations in GT transitions and in astrophysical observations.
