2005/10/19 by Saibal Ray, Utpal Mukhopadhyay, S. B. Dutta Choudhury · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #astro-ph
paper · pdf · doi:10.1142/s0218271807011097
published as Int.J.Mod.Phys.D16:1791-1802,2007 · Latex, 6 pages
arxiv created 2005/10/19 · openalex publication_date 2007/11/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Two phenomenological models of Λ, viz. [Formula: see text] and [Formula: see text], are studied under the assumption that G is a time-variable parameter. Both models show that G is inversely proportional to time, as suggested earlier by others, including Dirac. The models considered here can be matched with observational results by properly tuning the parameters of the models. Our analysis shows that the [Formula: see text] model corresponds to a repulsive situation and hence correlates with the present status of the accelerating Universe. The other model, [Formula: see text], is in general attractive in nature. Moreover, it is seen that due to the combined effect of time-variable Λ and G the Universe evolved with acceleration as well as deceleration. Deceleration indicates a "big crunch".