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arXiv · 0707.3148

Decaying Dark Energy in Higher-Dimensional Gravity

J. M. Overduin·P. S. Wesson·B. Mashhoon
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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.

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J. M. Overduin, P. S. Wesson, B. Mashhoon. 2007-07-20. Decaying Dark Energy in Higher-Dimensional Gravity. https://doi.org/10.1051/0004-6361:20077670

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