José Sande Lemos

CENTRA - Instituto Superior Técnico

Quasiblack holes with pressure

A class of electrically charged systems with pressure in general relativity arises when the gravitational potential and the electric potential obey a generalized Weyl relation, which we call the Weyl-Guilfoyle relation. For both, Weyl and Weyl-Guilfoyle relations, the electrically charged fluid, if present, may have nonzero pressure. Fluids obeying the Weyl-Guilfoyle relation are called Weyl-Guilfoyle fluids. These have very interesting features. In this talk we show some new properties of Weyl-Guilfoyle fluids, in particular, a relation necessarily obeyed by the matter fields. In addition, these fluids, under assumption of spherical symmetry, exhibit solutions which can be matched to the electrovacuum Reissner-Nordstrom spacetime to yield global asymptotically flat stars. We show that a particular spherically symmetric class of stars found by Guilfoyle has a well behaved limit which corresponds to a quasiblack hole with pressure, i.e., in which the fluid inside the horizon has electric charge and pressure. The main physical properties of such charged stars and quasiblack holes with pressure are analyzed.