Observational constraints on generalized Proca theories
(28 pages)

Comparing a MarkovChainMonteCarlo simulation of the de Sitter attractor in generalized Proca theory with a variety of cosmological data (CMB, BAO, SNIa, lowredshift H), it is shown that the model (which has a modified dark energy equation of state) is favoured over LCDM. One can also study perturbations, and impose noghost and stability conditions, as well as conditions from the galactic power spectrum of redshiftspace distortions.

An only indirectly observed vector field is no less natural or expected than an only indirectly observed scalar field (like the inflaton, or a dark energy field). It is therefore important to compare general vectortensor EFTs with cosmological to data, to see how they fare compared with (more conventional) scalartensor models, and with the concordance model.
