Einstein-Cartan, Bianchi I and the Hubble Diagram

TL;DR

This paper explores whether incorporating torsion through Einstein-Cartan gravity and anisotropy via Bianchi I metrics can explain dark matter effects observed in supernova Hubble diagrams, but finds limited success.

Contribution

It introduces a model combining Einstein-Cartan torsion and Bianchi I anisotropy to address dark matter in cosmology, extending previous standard models.

Findings

Best fit dust density Omega_{m0} = 27% ± 5%

Model's failure quantified by dust fraction

Limited success in explaining dark matter

Abstract

We try to solve the dark matter problem in the fit between theory and the Hubble diagram of supernovae by allowing for torsion via Einstein-Cartan's gravity and for anisotropy via the axial Bianchi I metric. Otherwise we are conservative and admit only the cosmological constant and dust. The failure of our model is quantified by the relative amount of dust in our best fit: Omega_{m0}= 27 % +/- 5 % at 1 sigma level.