Non-Abelian Einstein-Born-Infeld-Dilaton Cosmology

TL;DR

This paper explores a non-abelian Einstein-Born-Infeld-Dilaton cosmological model, revealing how gauge field-dilaton interactions and non-universal couplings can lead to cosmic acceleration, differing from standard tensor-scalar theories.

Contribution

It introduces a cosmological framework for non-abelian Einstein-Born-Infeld-Dilaton theory, analyzing the effects of non-universal couplings and gauge field dynamics on cosmic acceleration.

Findings

Evidence of cosmic acceleration in the model.

Non-universality of gravitational coupling affects evolution.

Gauge field dynamics influence acceleration mechanisms.

Abstract

The non-abelian Einstein-Born-Infeld-Dilaton theory, which rules the dynamics of tensor-scalar gravitation coupled to a $su(2)$-valued gauge field ruled by Born-Infeld lagrangian, is studied in a cosmological framework. The microscopic energy exchange between the gauge field and the dilaton which results from a non-universality of the coupling to gravity modifies the usual behaviour of tensor-scalar theories coupled to matter fluids. General cosmological evolutions are derived for different couplings to gravitation and a comparison to universal coupling is highlighted. Evidences of cosmic acceleration are presented when the evolution is interpreted in the Jordan physical frame of a matter respecting the weak equivalence principle. The importance for the mechanism of cosmic acceleration of the dynamics of the Born-Infeld gauge field, the attraction role of the matter fluid and the non-universality of the gravitational couplings is briefly outlined.