2008/09/02 by Krzysztof Bolejko, P. D. Lasky, Paul Lasky
Physics and Astronomy · #Astrophysics #Astrophysics and Star Formation Studies #Baryon acoustic oscillations #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Dark energy #Gravitational singularity #Mechanics #Physics #Quantum mechanics #Shell (structure) #Solar and Space Plasma Dynamics #astro-ph #gr-qc
paper · pdf · doi:10.1111/j.1745-3933.2008.00555.x
published as MNRAS 391, L59 (2008) · 5 pages, 3 figures. Accepted for publication in MNRAS
arxiv created 2008/09/02 · openalex publication_date 2008/10/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract Inhomogeneous cosmological models have recently become a very interesting alternative to standard cosmology. This is because these models are able to fit cosmological observations without the need for dark energy. However, due to inhomogeneity and pressureless matter content, these models can suffer from shell-crossing singularities. These singularities occur when two shells of dust collide with each other leading to infinite values of the density. In this Letter, we show that if inhomogeneous pressure is included then these singularities can be prevented from occurring over the period of structure formation. Thus, a simple incorporation of a gradient of pressure allows for more comprehensive studies of inhomogeneous cosmological models and their application to cosmology.