2008/12/31 by R. Chan, M.F.A. da Silva, M. F. A. da Silva +3 · 2 citations
Physics and Astronomy · #Accretion (finance) #Astrophysics #Black Holes and Theoretical Physics #Black hole (networking) #Bounded function #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Dark energy #Equation of state #Excursion #Mathematical analysis #Mathematical physics #Metric expansion of space #Perfect fluid #Phantom energy #Physics #Quantum mechanics #Relativity and Gravitational Theory #Schwarzschild radius #Shell (structure) #gr-qc
paper · pdf · doi:10.1088/1475-7516/2009/03/010
published as JCAP 0903:010,2009 · 35 pages, 43 figures, added some clarifying texts and corrected some typos, accepted for publication in JCAP
arxiv created 2009/02/11 · openalex publication_date 2009/03/05 · arxiv updated 2012/10/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Dynamical models of prototype gravastars made of anisotropic dark energy fluid are constructed, in which an infinitely thin spherical shell of a perfect fluid with the equation of state p = (1−γ)σ divides the whole spacetime into two regions, the internal region is filled with an anisotropic dark energy fluid, and the external region is the Schwarzschild. It is found that in some cases the models represent the ``bounded excursion'' stable gravastars, where the thin shell is oscillating between two finite radii, while in other cases they collapse until the formation of black holes or normal stars. In the phase space, the region for the ``bounded excursion'' gravastars is very small in comparison to that of black holes, but not empty, as found in our previous papers. Therefore, although the existence of gravastars can not be completely excluded from current analysis, the opposite is not possible either, that is, even if gravastars exist, they do not exclude the existence of black holes.