SEZIONE DI FIRENZE
Seminario di David Rodriguez (Oviedo University)
Abstract: According to common lore, Equations of State of field theories with gravity duals tend to be soft, with speeds of sound either below or around the conformal value. This has important consequences in particular for the physics of compact stars, where the detection of two solar mass neutron stars has been shown to require very stiff equations of state. In this talk, I show that no speed limit exists for holographic models at finite density, explicitly constructing examples where the speed of sound becomes arbitrarily close to that of light. This opens up the possibility of building hybrid stars that contain quark matter obeying a holographic equation of state in their cores.