C. J. A. P. Martins, C. M. J. Marques, C. B. D. Fernandes, J. S. J. S. Oliveira, D. A. R. Pinheiro, B. A. R. Rocha
Abstract
We present a comparative analysis of current observational constraints on three recently discussed alternative models for explaining the low-redshift acceleration of the universe: the so-called steady-state torsion model, the generalized coupling model, and the scale invariant model by Maeder (an example of a broader class which we also briefly study). These are compared to the traditional parameterization of Chevallier, Polarski and Linder. Each of the candidate models is studied under two different assumptions: as genuine alternatives to ΛCDM (where a new degree of freedom would be expected to explain the recent acceleration of the universe without any cosmological constant) and as parametric extensions of ΛCDM (where both a cosmological constant and the new mechanism can coexist, and the relative contributions of both are determined by the data). Our comparative analysis suggests that, from a phenomenological point of view, all such models neatly divide into two classes, with different observational consequences.
Proceedings of the MG16 Meeting on General Relativity
Remo Ruffini, Gregory Vereshchagin
World Scientific Publishing Co Pte Ltd, Page 907
2023 March
