Skip navigation.

Institute for the Physics and Mathematics of the UniverseWPI

IPMU Sub-group Seminar

Date: August 28, 2008, 13:30 - 15:00
Place: Seminar Room at IPMU Prefab. B, Kashiwa Campus of the University of Tokyo
Speaker: Andrei Frolov (Simon Fraser University)
Title: A Singularity Problem with f(R) Dark Energy [PDF]
Abstract: I will talk about a curvature singularity problem appearing on non-linear level that generally plagues f(R) models that modify Einstein gravity in the infrared. It is caused by the fact that for the effective scalar degree of freedom, the curvature singularity is at a finite field value and energy level, and can be easily accessed by the field dynamics in the presence of matter. Consequences for observational viability are grave: regular static solutions for neutron stars do not exist in many IR-modified f(R) models. I will discuss whether the theory can be saved by an UV-completion.