Torsion driving cosmic expansion

Abstract

We study a cosmological model based on the canonical Hamiltonian transformation theory. Using a linear-quadratic approach for the free gravitational De Donder–Weyl Hamiltonian H_textrm{Gr}, the model contains terms describing a deformation of an AdS spacetime and a fully anti-symmetric torsion in addition to Einstein’s theory. The resulting extension of the Einstein–Cartan theory depends on two initially unknown constants, Omega _textrm{g} and Omega _textrm{s}. Given an appropriate choice of these parameters resulting from the analysis of asymptotics, numerical calculations were performed with Omega _mathrm {Lambda } = 0. Values from the Planck Collaboration (Aghanim in Cosmol Parameters 641, 6, 2020) were used for all other required cosmological parameters. In this way, it is shown that torsion can explain phenomena commonly attributed to dark energy, and thus can replace Einstein’s cosmological constant.