On the sound speed in hyperonic stars

Abstract We build upon the remarkable, model independent constraints on the equation of state of dense baryonic matter established recently by Annala et al. [1] . Using the quark-meson coupling model, an approach to nuclear structure based upon the self-consistent adjustment of hadron structure to the local meson fields, we show that, once hyperons are allowed to appear in dense matter in β-equilibrium, the equation of state is consistent with those constraints. As a result, while one cannot rule out the occurrence of quark matter in the cores of massive neutron stars, the available constraints are also compatible with the presence of hyperons.