Multidimensional perfect fluid cosmology with stable compactified internal dimensions

TL;DR

This paper explores multidimensional cosmological models with perfect fluids and a cosmological constant, demonstrating conditions for stable internal dimensions and realistic external universe behavior consistent with observations.

Contribution

It introduces a class of perfect fluids that enable stable compactification of internal spaces in multidimensional cosmology.

Findings

Stable compactification achieved for specific perfect fluid parameters.

External space dynamics align with Friedmann model.

Restrictions identified for observational consistency.

Abstract

Multidimensional cosmological models in the presence of a bare cosmological constant and a perfect fluid are investigated under dimensional reduction to 4-dimensional effective models. Stable compactification of the internal spaces is achieved for a special class of perfect fluids. The external space behaves in accordance with the standard Friedmann model. Necessary restrictions on the parameters of the models are found to ensure dynamical behavior of the external (our) universe in agreement with observations.