Nonlinear multidimensional gravity and the Australian dipole

TL;DR

This paper develops a multidimensional gravity model linking variations in fundamental constants, including the fine structure constant, to the dynamics of extra dimensions, explaining observed spatial and temporal variations.

Contribution

It introduces a unified method connecting variations of multiple fundamental constants to extra-dimensional dynamics within nonlinear multidimensional gravity theories.

Findings

A specific model explaining observed variations of alpha in space and time.

The model incorporates a FRW cosmology with accelerated expansion and inhomogeneous initial conditions.

The approach unifies the explanation of different fundamental constant variations.

Abstract

The existing observational data on possible variations of fundamental physical constants (FPC) confirm more or less confidently only a variability of the fine structure constant $\alpha$ in space and time. A model construction method is described, where variations of $\alpha$ and other FPCs (including the gravitational constant $G$) follow from the dynamics of extra space-time dimensions in the framework of curvature-nonlinear multidimensional theories of gravity. An advantage of this method is a unified approach to variations of different FPCs. A particular model explaining the observable variations of $\alpha$ in space and time has been constructed. It comprises a FRW cosmology with accelerated expansion, perturbed due to slightly inhomogeneous initial data.