Modified geodetic brane cosmology

TL;DR

This paper investigates a modified geodetic brane cosmology model incorporating extrinsic curvature corrections, leading to a generalized Friedmann equation that can describe accelerated cosmic expansion depending on model parameters.

Contribution

It introduces a new correction term in geodetic brane gravity, deriving a generalized Friedmann equation and analyzing its implications for cosmic acceleration.

Findings

The model can produce self-accelerated expansion without dark energy.

The behavior depends on the eta-parameter and matter content.

It resembles DGP brane cosmology in certain limits.

Abstract

We explore the cosmological implications provided by the geodetic brane gravity action corrected by an extrinsic curvature brane term, describing a codimension-1 brane embedded in a 5D fixed Minkowski spacetime. In the geodetic brane gravity action, we accommodate the correction term through a linear term in the extrinsic curvature swept out by the brane. We study the resulting geodetic-type equation of motion. Within a Friedmann-Robertson-Walker metric, we obtain a generalized Friedmann equation describing the associated cosmological evolution. We observe that, when the radiation-like energy contribution from the extra dimension is vanishing, this effective model leads to a self-(non-self)-accelerated expansion of the brane-like universe in dependence on the nature of the concomitant \beta-parameter associated with the correction, which resembles an analogous behaviour in the DGP brane cosmology. Several possibilities in the description for the cosmic evolution of this model are embodied and characterized by the involved density parameters related in turn to the cosmological constant, the geometry characterizing the model, the introduced \beta-parameter as well as the dark like-energy and the matter content on the brane.