Colóquio: Platypus Stars: Vacuum Stars as an Alternative to Gravastars (Gonzalo J. Olmo)
Ciclo de Colóquios 2026.1
Colóquio #06
“Platypus Stars: Vacuum Stars as an Alternative to Gravastars”
Prof. Dr. Gonzalo J. Olmo
Department of Theoretical Physics & IFIC, University of Valencia – CSIC
Sexta-feira, 08 de maio de 2026, às 14h, na sala 201 do Departamento de Física/CCEN.
RESUMO: Gravastars are often presented as horizonless alternatives to black holes, supported by the energy and pressure associated with a cosmological constant. In this talk, I will show that, if vacuum energy is treated as truly empty space (rather than as a cosmological constant), it is possible to construct a new type of stellar object based on this premise within General Relativity, using the Tolman–Oppenheimer–Volkoff (TOV) equations. I will describe the structural properties of these objects, discuss aspects of the matching conditions involved, and analyze their compactness as well as the behavior of null geodesics in these geometries.
