Correspondence between Loop-inspired and Braneworld Cosmology

TL;DR

This paper establishes a correspondence between loop quantum cosmology and braneworld scenarios by comparing their modified Friedmann equations, enabling a unified view of these quantum gravity approaches and their cosmological implications.

Contribution

It demonstrates a dynamical correspondence between loop-inspired and braneworld cosmologies at the effective field equations level.

Findings

Qualitative features of both approaches can be compared.

Concrete relationships between different cosmological backgrounds are shown.

Framework for viewing braneworlds as constrained Hamiltonian systems.

Abstract

Braneworld scenarios are motivated by string/M-theory and can be characterized by the way in which they modify the conventional Friedmann equations of Einstein gravity. An alternative approach to quantum gravity, however, is the loop quantum cosmology program. In the semi-classical limit, the cosmic dynamics in this scenario can also be described by a set of modified Friedmann equations. We demonstrate that a dynamical correspondence can be established between these two paradigms at the level of the effective field equations. This allows qualitatively similar features between the two approaches to be compared and contrasted as well as providing a framework for viewing braneworld scenarios in terms of constrained Hamiltonian systems. As concrete examples of this correspondence, we illustrate the relationships between different cosmological backgrounds representing scaling solutions.