Abstract
Abstract
We confront massive Proca-Nuevo gravity with cosmological
observations. The former is a non-linear theory involving a massive spin-1
field, that can be extended incorporating operators of the Generalized Proca
class, and when coupled to gravity it can be covariantized in a way that
exhibits consistent and ghost-free cosmological solutions, without experiencing
instabilities and superluminalities at the perturbative level.
When applied at a cosmological framework it induces extra terms in the
Friedmann equations, however due to the special non-linear construction the
field is eliminated in favor of the Hubble function. Thus, the resulting
effective dark energy sector is dynamical, however it contains
the same number of free parameters with the ΛCDM concordance model.
We use data from Supernovae Ia (SNIa) and Cosmic Chronometers
(CC) observations and we construct the corresponding likelihood-contours for
the free parameters. Interestingly enough, application of various information
criteria, such as AIC, BIC and DIC, shows that the scenario of massive
Proca-Nuevo gravity, although having exactly the same number of free
parameters
with ΛCDM paradigm, it is more efficient in fitting the data.
Finally, the reconstructed dark-energy equation-of-state parameter
shows statistical compatibility
with the model-independent, data-driven reconstructed one.