The holographic induced gravity model with a Ricci dark energy: smoothing the little rip and big rip through Gauss-Bonnet effects?

TL;DR

This paper explores a holographic brane-world model with Ricci dark energy and Gauss-Bonnet effects, showing how these factors influence late-time acceleration and singularity avoidance in the universe.

Contribution

It introduces a novel holographic brane-world model incorporating Ricci dark energy and Gauss-Bonnet terms, analyzing their effects on cosmic singularities and late-time acceleration.

Findings

Gauss-Bonnet term can prevent big rip and little rip singularities.

The holographic parameter determines the universe's asymptotic behavior.

Certain parameter ranges lead to singularity avoidance in the model.

Abstract

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.