Nuclear, Particle, Astroparticle and Cosmology (NUPAC) Seminars
The Cosmological Constant and the Characteristic Development of Trapped Surfaces
Presented by Paul Demmie, UNM
The concept of a trapped surface provides a precise characterization of gravitational collapse that has proceeded beyond the point of no return, resulting in a black hole. The cosmological constant is a model of dark energy that is one explanation for the accelerated expansion of the universe. Therefore, because of its importance, we examined spherically-symmetric spacetimes with a cosmological constant to determine its impact on the characteristic development of trapped surfaces. The principal results of this study are relationships between the mass (m) and the cosmological constant (Λ) that give necessary and sufficient conditions for trapped surfaces to develop to the future of a branch of a perfect null hypersurface. For the cosmological constant obtained from the Planck-satellite data, there is a maximum mass for a black hole. We argue that this result implies that our universe is too massive to be closed and bounded. We determined the value for the cosmological constant for a Planck-mass black hole and showed that it is 120 orders of magnitude larger than the cosmological constant obtained from the Planck-satellite data.
2:00 pm, Tuesday, September 20, 2022
PAIS-3205, PAIS
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