[SEMINARI] SEMINAR: Olga Mena, Inverse Curvature Gravity

[German Rodrigo Garcia]

Inverse Curvature Gravity

Olga Mena
Fermilab
Wednesday, 18 of October of 2006     15:00 PM
IFIC's Seminar

Abstract

We show that the current accelerated expansion of the Universe can be 
explained without resorting to dark energy. Models of generalized modified 
gravity, with inverse powers of the curvature can have late time 
accelerating attractors without conflicting with solar system experiments. 
We have solved the Friedman equations for the full dynamical range of the 
evolution of the Universe. This allows us to perform a detailed analysis 
of Supernovae data in the context of such models that results in an 
excellent fit. Hence, inverse curvature gravity models represent an 
example of phenomenologically viable models in which the current 
acceleration of the Universe is driven by curvature instead of dark 
energy. If we further include constraints on the current expansion rate of 
the Universe from the Hubble Space Telescope and on the age of the 
Universe from globular clusters, we obtain that the matter content of the 
Universe is 0.07 <= omega_m <= 0.21 (95% Confidence). Hence the inverse 
curvature gravity models considered can not explain the dynamics of the 
Universe just with a baryonic matter component.