A cosmic vector for dark energy

TL;DR

This paper proposes a vector field model for dark energy that explains cosmic acceleration without fine-tuning, fits supernova data well, and makes testable predictions distinguishing it from standard cosmology.

Contribution

It introduces a novel vector field model for dark energy that avoids fine-tuning and the cosmic coincidence problem, with precise data fitting and testable predictions.

Findings

Fits supernova data with high precision

Avoids fine-tuning and initial condition problems

Predicts observable differences from standard cosmology

Abstract

In this work we show that the presence of a vector field on cosmological scales could explain the present phase of accelerated expansion of the universe. The proposed theory contains no dimensional parameters nor potential terms and does not require unnatural initial conditions in the early universe, thus avoiding the so called cosmic coincidence problem. In addition, it fits the data from high-redshift supernovae with excellent precision, making definite predictions for cosmological parameters. Upcoming observations will be able to clearly discriminate this model from standard cosmology with cosmological constant.