Abstract
Title: "Brane-world induced gravity: early and late-time behaviour"
Abstract:
In this talk, we will review the induced gravity brane-world
scenario. On the one hand, we will show how the induced gravity affects the
early-time evolution of the brane through corrections to the Randall-Sundrum
type cosmology. In particular, we will analyse the effect of these corrections
in the amplitude of the primordial gravitational waves on large scale as well
as the amplitude of the scalar perturbations on the brane (with respect to the
Randall-Sundrum case and the standard 4-dimensional case). The analysis is
performed on the extreme slow-roll limit for an inflaton confined to the
brane. On the other hand, the induced gravity, in the context of the
Dvali-Gabadadze-Porrati model, can describe the late-time speed up of the
universe or induce a mimicry of a phantom-like behaviour on the brane. The
mimicry is achieved without invoking any matter that violates the null energy
condition on the brane and is based in defining an effective energy density
which corresponds to a balance between dark energy and geometrical effects.
Depending on the dynamical character of the dark energy, this effective energy
density can either mimic a phantom-like behaviour or even a crossing of the
cosmological constant line.