La Trobada: Theoretical bounds on the tensor-to-scalar ratio in the cosmic microwave background

por Lotfi Boubekeur (ICTP, Trieste)

miércoles 8 may. 2013 11:30 → 12:30 Europe/Madrid

Sala Seminarios IFIC (Edf. Institutos de Investigación)

Tensor modes in the cosmic microwave background are one of the most robust signatures of inflation. We derive theoretical bounds on the tensor fraction, as a generalization of the well-known Lyth bound. Under reasonable assumptions, the new bounds are at least two orders of magnitude stronger than the original one. We comment on a previously derived generalization, the so-called Efstathiou-Mack relationship. We also derive a new absolute upper bound on tensors using de Sitter entropy bounds.