The Friedmann Universe and Compact Internal Spaces in Higher-Dimensional Gravity Theories

TL;DR

This paper explores higher-dimensional gravity theories with extended Gauss-Bonnet terms, showing that certain compactifications can naturally lead to a zero four-dimensional cosmological constant, with implications for Kaluza-Klein cosmology.

Contribution

It introduces a generalized Einstein gravity in higher dimensions with Gauss-Bonnet terms that achieve a vanishing 4D cosmological constant through symmetric compactification.

Findings

Maximal symmetric compactification yields zero 4D cosmological constant

Generalized Kaluza-Klein cosmology analyzed in this framework

Extended Gauss-Bonnet density governs the higher-dimensional gravity theories

Abstract

We consider gravity theories in $4+N$ dimensions which are governed by the Lagrangian written as an extended Gauss-Bonnet density. We can find a naturally generalized Einstein gravity where the maximal symmetric compactification leads to vanishing four-dimensional cosmological constant in the static limit. A later stage in the generalized Kaluza-Klein cosmology is also examined.