Inflationary gravitational waves and exotic pre Big Bang Nucleosynthesis
  cosmology
  According to the most popular scenario, the early Universe should have
experienced an accelerated expansion phase, called Cosmological Inflation,
after which the standard Big Bang Cosmology would have taken place giving rise
to the radiation-dominated epoch. However, the details of the inflationary
scenario are far to be completely understood. Thus, in this paper we study if
possible additional (exotic) cosmological phases could delay the beginning of
the standard Big Bang history and alter some theoretical predictions related to
the inflationary cosmological perturbations, like, for instance, the order of
magnitude of the tensor-to-scalar ratio $r$.
