Particles and gravitons creation after inflation from a 5D vacuum

We use the Bogoliubov formalism to study both, particles and gravitons creation at the reheating epoch, after a phase transition from inflation to a radiation dominated universe. The modes of the inflaton field fluctuations and the scalar fluctuations of the metric at the end of inflation are obtained by using a recently introduced formalism related to the Induced Matter theory of gravity. The interesting result is that the number of created particles is bigger than ${10}^{90}$ on cosmological scales. Furthermore, the number of gravitons are nearly ${10}^{-17}$ times smaller than the number of created particles. In both cases, these numbers rapidly increases on cosmological scales.