2023/01/14 by José M. M. Senovilla, Senovilla, José M M
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Mathematical Physics (math-ph) #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.2301.05913
openalex publication_date 2023/01/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It has been long known that in spacetimes with a positive cosmological constant Λ>0 the area of spatially stable marginally trapped surfaces (MTSs) has a finite upper bound given by 4π/Λ. In this paper I show that any such spacetime containing spatially stable MTSs with area approaching indefinitely that bound acquire universal properties generically. Specifically, they all possess \em generalized `holographic screens' (i.e. marginally trapped tubes) foliated by MTSs of spherical topology, composed of a dynamical horizon portion and a timelike membrane portion that meet at a distinguished round sphere S with constant Gaussian curvature K =Λ -- and thus of maximal area 4π/Λ. All future (past) generalized holographic screens containing S change signature at S, and all of them continue towards the past (future) with non-decreasing (non-increasing) area of their MTSs. A future (past) singularity obtains. For the future case, these `ultra-massive spacetimes' (arXiv:2209.14585) may be more powerful than black holes, as they can overcome the repulsive Λ-force and render the spacetime as a collapsing universe without event horizon enclosing those generalized holographic screens. It is remarkable that these behaviours do not arise if Λ is non-positive. The results have radical implications on black hole mergers and on very compact objects accreting mass from their surroundings -- if Λ>0.