Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chiral symmetry restoration and the $\Delta$ matter formation in neutron
  stars   We analyze the effects of chiral symmetry restoration in hadronic matter,
including the lowest-lying baryonic resonance $\Delta$ based on the parity
doublet model. We study the role of $\Delta$ and its chiral partner on the
equation of state (EoS) of dense matter under neutron star (NS) conditions of
$\beta$-equilibrium and charge neutrality. We find that the softening of the
EoS driven by the early onset of $\Delta$ matter due to partial restoration of
chiral symmetry allows accommodating the modern multi-messenger astrophysical
constraints on the mass, radius, and tidal deformability. The softening above
the saturation density is accompanied by subsequent stiffening at high
densities. We also find that the matter composition in the NS cores may be
different upon variations of the repulsive interactions of $\Delta$ baryons in
hadronic matter.

5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio