2 research outputs found
The holographic induced gravity model with a Ricci dark energy: smoothing the little rip and big rip through Gauss-Bonnet effects?
We present an holographic brane-world model of the Dvali-Gabadadze-Porrati
(DGP) scenario with and without a Gauss-Bonnet term (GB) in the bulk. We show
that an holographic dark energy component with the Ricci scale as the infra-red
cutoff can describe the late-time acceleration of the universe. In addition, we
show that the dimensionless holographic parameter is very important in
characterising the DGP branches, and in determining the behaviour of the Ricci
dark energy as well as the asymptotic behaviour of the brane. On the one hand,
in the DGP scenario the Ricci dark energy will exhibit a phantom-like behaviour
with no big rip if the holographic parameter is strictly larger than 1/2. For
smaller values, the brane hits a big rip or a little rip. On the other hand, we
have shown that the introduction of the GB term avoids the big rip and little
rip singularities on both branches but cannot avoid the appearance of a big
freeze singularity for some values of the holographic parameter on the normal
branch, however, these values are very unlikely because they lead to a very
negative equation of state at the present and therefore we can speak in
practice of singularity avoidance. At this regard, the equation of state
parameter of the Ricci dark energy plays a crucial role, even more important
than the GB parameter, in rejecting the parameter space where future
singularities appear.Comment: 11 pages, 8 figures. RevTex4-1. Comments and references added.
Version accepted in PR