Cosmic vector for dark energy: constraints from SN, CMB and BAO

TL;DR

This paper investigates a vector field model for dark energy, analyzing constraints from supernovae, CMB, and BAO data, revealing a preference for a closed universe and tensions between datasets.

Contribution

It provides a detailed constraint analysis of vector dark energy models with spatial curvature using multiple cosmological datasets.

Findings

CMB data excludes a flat universe in this model

CMB predicts a closed universe for spatial sections

Tension exists between SNIa and BAO measurements

Abstract

It has been recently shown that the presence of a vector field over cosmological scales could explain the observed accelerated expansion of the universe without introducing neither new scales nor unnatural initial conditions in the early universe, thus avoiding the coincidence problem. Here, we present a detailed analysis of the constraints imposed by SNIa, CMB and BAO data on the vector dark energy model with general spatial curvature. We find that contrary to standard cosmology, CMB data excludes a flat universe for this model and, in fact, predicts a closed geometry for the spatial sections. We see that CMB and SNIa Gold data are perfectly compatible at the 1-sigma level, however SNIa Union dataset exhibits a 3-sigma tension with CMB. The same level of tension is also found between SNIa and BAO measurements.