Astrophysics, abstract
astro-ph/0605450

From: Ruth Lazkoz [view email]

Date: Thu, 18 May 2006 11:29:19 GMT (38kb)

Crossing the phantom divide without phantom matter

Authors: Luis P. Chimento, Ruth Lazkoz, Roy Maartens, Israel Quiros

Comments: 5 pages, 5 figures, revtex4

A class of braneworld models can lead to phantom-like acceleration of the late universe, but without the need for any phantom matter. In the simplest models, the universe contains only cold dark matter and a cosmological constant. We generalize these models by introducing a quintessence field. The new feature in our models is that quintessence leads to a crossing of the phantom divide, $w=-1$. This is a purely gravitational effect, and there is no phantom instability. Furthermore, the Hubble parameter is always decreasing, and there is no big rip singularity in the future.

http://arxiv.org/abs/astro-ph/0605450