Decaying Dark Energy in Higher-Dimensional Gravity

TL;DR

This paper investigates higher-dimensional gravity models with decaying dark energy, using cosmological data to constrain the models and explore their implications for universe's age, structure formation, and supernova observations.

Contribution

It provides observational constraints on higher-dimensional gravity theories with decaying dark energy, focusing on the cosmological length scale parameter L.

Findings

Lower limits on the length scale L from age and supernova data

Decaying dark energy affects universe's age and structure formation

Potential for tighter constraints with improved supernova measurements

Abstract

We use data from observational cosmology to put constraints on higher-dimensional extensions of general relativity in which the effective four-dimensional dark-energy density (or cosmological "constant") decays with time. In particular we study the implications of this decaying dark energy for the age of the universe, large-scale structure formation, big-bang nucleosynthesis and the magnitude-redshift relation for Type Ia supernovae. Two of these tests (age and the magnitude-redshift relation) place modest lower limits on the free parameter of the theory, a cosmological length scale L akin to the de Sitter radius. These limits will improve if experimental uncertainties on supernova magnitudes can be reduced around z=1.