3-form inflation in Randall-Sundrum II

It has been shown in the last few years that 3-form fields present viable cosmological solutions for inflation and dark energy with particular observable signatures distinct from those of canonical single scalar field inflation. The aim of this work is to explore the dynamics of a single 3-form in five dimensional Randall-Sundrum II braneworld scenario, in which a 3-form is confined to the brane and only gravity propagates in the bulk. We compare the solutions with the standard four dimensional case already studied in the literature. In particular, we evaluate how the spectral index and the ratio of tensor to scalar perturbations are influenced by the presence of the bulk and put constraints on the parameters of the models in the light of the recent Planck 2015 data.