  I discuss three topics in physics of massive (two solar-mass and larger)
neutron stars containing deconfined quark matter: (i) the equation of state of
deconfined dense quark matter and its color superconducting phases, (ii) the
thermal evolution of stars with quark cores, (iii) color-magnetic flux tubes in
type-II superconducting quark matter and their dynamics driven by Aharonov-Bohm
interactions with unpaired fermions.
