The universe is accelerating. Do we need a new mass scale?
arXiv:0910.3949 · doi:10.1016/j.physletb.2010.04.061
Abstract
We try to address quantitatively the question whether a new mass is needed to fit current supernovae data. For this purpose, we consider an infra-red modification of gravity that does not contain any new mass scale but systematic subleading corrections proportional to the curvature. The modifications are of the same type as the one recently derived by enforcing the "Ultra Strong Equivalence Principle" (USEP) upon a Friedmann-Lemaitre-Robertson-Walker universe in the presence of a scalar field. The distance between two comoving observers is altered by these corrections and the observations at high redshift affected at any time during the cosmic evolution. While the specific values of the parameters predicted by USEP are ruled out, there are regions of parameter space that fit SnIa data very well. This allows an interesting possibility to explain the apparent cosmic acceleration today without introducing either a dark energy component or a new mass scale.
8 pages, 3 figures. Final version: references added.
References in corpus (16)
- Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
- Dynamics of dark energy
- Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
- Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
- Improved Cosmological Constraints from New, Old and Combined Supernova Datasets
- Disappearing cosmological constant in f(R) gravity
- Improved Dark Energy Constraints from ~100 New CfA Supernova Type Ia Light Curves
- Measuring the Baryon Acoustic Oscillation scale using the SDSS and 2dFGRS
- Conditions for the cosmological viability of f(R) dark energy models
- Observational signatures of f(R) dark energy models that satisfy cosmological and local gravity constraints
- The Cosmology of f(R) Gravity in the Metric Variational Approach
- Degravitation of the Cosmological Constant and Graviton Width
- The cosmological constant from the ghost. A toy model
- Gauge invariant averages for the cosmological backreaction
- SNLS data are consistent with acceleration at z=3
- The IR-Completion of Gravity: What happens at Hubble Scales?