Decaying dark energy in higher-dimensional gravity
Gravity Probe B, Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085, USA e-mail: email@example.com
2 Astronomy Group, Department of Physics, University of Waterloo, Waterloo, Ontario N2L 3G1, USA
3 Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA
Accepted: 3 August 2007
Aims.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.
Methods.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.
Results.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 .
Key words: cosmology: theory / stars: supernovae: general
© ESO, 2007