2005/05/12 by Luis P. Chimento, Ruth Lazkoz · 2 citations
Physics and Astronomy · #Acceleration #Advanced Differential Geometry Research #Astrophysics #Black Holes and Theoretical Physics #Chaplygin gas #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Dual polyhedron #Duality (order theory) #Gravitation #Gravitational singularity #Mathematical physics #Physics #Pure mathematics #Quantum mechanics #Theoretical physics #Universe #astro-ph
paper · pdf · doi:10.1088/0264-9381/23/9/027
published as Class.Quant.Grav.23:3195-3204,2006 · 5 pages, revtex4
arxiv created 2005/05/12 · openalex publication_date 2006/04/07 · arxiv updated 2014/10/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We consider modifications to the Friedmann equation motivated by recent proposals along these lines pursuing an explanation to the observed late time acceleration. Here we show that these approaches can be framed within a theory with modified gravity, and we discuss the construction of the duals of the cosmologies generated within that framework. We then investigate the modifications required to generate extended, generalized and modified Chaplygin cosmologies, and then show that their duals belong to a larger family of cosmologies we call enlarged Chaplygin cosmologies. Finally, by letting the parameters of these models take values not earlier considered in the literature we show that some representatives of that family of cosmologies display sudden future singularities. This fact indicates that the behaviour of these spacetimes is rather different from that of generalized or modified Chaplygin gas cosmologies. This reinforces the idea that modifications of gravity can be responsible for unexpected evolutionary features in the universe.