Symmetries of Vector Perturbations during the de Sitter Epoch
  We analyze the class of models where a suitable coupling between the inflaton
field and the vector field gives rise to scale-invariant vector perturbations.
We exploit the fact that the de Sitter isometry group acts as conformal group
on the three-dimensional Euclidean space for the super-Hubble fluctuations in
order to characterize the correlators involving the inflaton and the vector
fields.
