Holographic quark matter and neutron stars
  We use a top-down holographic model for strongly interacting quark matter to study the properties of neutron stars. When the corresponding Equation of State (EoS) is matched with state-of-the-art results for dense nuclear matter, we consistently observe a first order phase transition at densities between two and seven times the nuclear saturation density. Solving the Tolman-Oppenheimer-Volkov equations with the resulting hybrid EoSs, we find maximal stellar masses in the excess of two solar masses, albeit somewhat smaller than those obtained with simple extrapolations of the nuclear matter EoSs. Our calculation predicts that no quark matter exists inside neutron stars. 
Carlos Hoyos, David Rodr\'iguez Fern\'andez, Niko Jokela, and Aleksi   Vuorinen
hep-ph astro-ph.HE hep-th