2010/05/31 by Antonio C. C. Guimarães, J. A. S. Lima, José Ademir S. Lima
Physics and Astronomy · #Acceleration #Astronomy #Astrophysics #COSMIC cancer database #Classical mechanics #Cosmic ray #Cosmology #Cosmology and Gravitation Theories #Dark energy #Galaxies: Formation, Evolution, Phenomena #Gamma-ray bursts and supernovae #General relativity #Luminosity #Luminosity distance #Metric expansion of space #Physics #Theoretical physics #astro-ph.CO
paper · pdf · doi:10.1088/0264-9381/28/12/125026
published as Class. Quantum Grav. 28 (2011) 125026 · 11 pages, 4 figures. Accepted for publication in Classical and Quantum Gravity
arxiv created 2011/04/26 · openalex publication_date 2011/05/27 · arxiv updated 2015/03/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
A possible slowing down of the cosmic expansion is investigated through a cosmographic approach. By expanding the luminosity distance to fourth order and fitting the SN Ia data from the most recent compilations (Union, Constitution and Union 2), the marginal likelihood distributions for the deceleration parameter today suggest a recent reduction of the cosmic acceleration and indicate that there is a considerable probability for q 0 > 0. Also in contrast to the prediction of the ΛCDM model, the cosmographic q ( z ) reconstruction permits a cosmic expansion history where the cosmic acceleration could already have peaked and be presently slowing down, which would imply that the recent accelerated expansion of the universe is a transient phenomenon. It is also shown that to describe a transient acceleration the luminosity distance needs to be expanded at least to fourth order. The present cosmographic results depend neither on the validity of general relativity nor on the matter–energy contents of the universe.