When scalar field is kinetically coupled to the Einstein tensor

Details When scalar field is kinetically coupled to the Einstein tensor When scalar field is kinetically coupled to the Einstein tensor

2010-02-22

arxiv.org/abs/1002.4035v7

JCAP 06 (2010) 023

Astronomy and Astrophysics

Astrophysics

General Relativity and Quantum Cosmology

12 pages, 17 figures. The sound speed is recalculated and the English improved. To appear in JCAP

Scientific paper

We explore the cosmic evolution of a scalar field with the kinetic term coupled to the Einstein tensor. We find that, in the absence of other matter sources or in the presence of only pressureless matter, the scalar behaves as pressureless matter and the sound speed of the scalar is vanishing. These properties enable the scalar field to be a candidate of cold dark matter. By also considering the scalar potential, we find the scalar field may play the role of both dark matter and dark energy. In this case, the equation of state of the scalar can cross the phantom divide, but this can lead to the sound speed becoming superluminal as it crosses the divide, and so is physically forbidden. Finally, if the kinetic term is coupled to more than one Einstein tensor, we find the equation of state is always approximately equal to -1 whether the potential is flat or not, and so the scalar may also be a candidate for the inflaton.

Affiliated with

Also associated with

No associations

Rating

When scalar field is kinetically coupled to the Einstein tensor does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with When scalar field is kinetically coupled to the Einstein tensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and When scalar field is kinetically coupled to the Einstein tensor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-373113