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arXiv · 1811.10012

Topology change and nuclear symmetry energy in compact-star matter

Xiang-Hai Liu·Yong-Liang Ma·Mannque Rho
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Abstract

We show that the cusp-like structure in the nuclear symmetry energy, a consequence of topology change, visible in the skyrmion lattice description of dense matter is extremely robust. It is present in the Skyrme model -- with the pion field only -- and is left unscathed by massive degrees of freedom such as the vector mesons $ρ$ and $ω$ and also the scalar meson introduced as a dilaton. It leads to the emergence of parity-doubling at the skyrmion-half-skyrmion transition and impacts on the nuclear symmetry energy "wilderness" landscape, weeding out roughly half of the wilderness. It is shown that a pseudo-conformal sound velocity arises at a precocious density at which the cusp is formed. It is suggested that the topology change, being robust, could impact on the tidal deformability observed in gravity waves

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Xiang-Hai Liu, Yong-Liang Ma, Mannque Rho. 2019-01-07. Topology change and nuclear symmetry energy in compact-star matter. https://doi.org/10.1103/physrevc.99.055808

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