Note on the emergence of cosmic space in modified gravities

TL;DR

This paper extends Padmanabhan's idea of emergent cosmic space to modified gravity theories like brane world, scalar-tensor, and f(R), successfully deriving the Friedmann equations in these contexts.

Contribution

It generalizes the emergent space paradigm to various modified gravity models, connecting holographic principles with cosmological equations.

Findings

Friedmann equations derived in brane world, scalar-tensor, and f(R) gravity.

Supports the universality of the emergent space concept across gravity theories.

Provides a new perspective on cosmic expansion in alternative gravity models.

Abstract

Intrigued by the holographic principle, Padmanabhan recently proposed a novel idea, saying that our cosmic space is emergent as cosmic time progresses. In particular, the expansion rate of the Universe is related to the difference between the surface degrees of freedom on the holographic horizon and the bulk degrees of freedom inside. In this note, we generalize this interesting paradigm to brane world, scalar-tensor gravity, and f(R) theory, respectively, and find that in the cosmological setting the Friedmann equations can be successfully derived.