A New Exponential Gravity

Abstract

We propose a new exponential f(R) gravity model with f(R)=(R-λc)e^{λ(c/R)^n} and n>3, λ\geq 1, c>0 to explain late-time acceleration of the universe. At the high curvature region, the model behaves like the \LambdaCDM model. In the asymptotic future, it reaches a stable de-Sitter spacetime. It is a cosmologically viable model and can evade the local gravity constraints easily. This model share many features with other f(R) dark energy models like Hu-Sawicki model and Exponential gravity model. In it the dark energy equation of state is of an oscillating form and can cross phantom divide line ω_{de}=-1. In particular, in the parameter range 3< n\leq 4, λ\sim 1, the model is most distinguishable from other models. For instance, when n=4, λ=1, the dark energy equation of state will cross -1 in the earlier future and has a stronger oscillating form than the other models, the dark energy density in asymptotical future is smaller than the one in the high curvature region. This new model can evade the local gravity tests easily when n>3 and λ>1.

12 pages, 8 figures

References in corpus (17)

• Dynamics of dark energy
• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
• Disappearing cosmological constant in f(R) gravity
• Class of viable modified $f(R)$ gravities describing inflation and the onset of accelerated expansion
• Dark Energy
• Dark energy in modified Gauss-Bonnet gravity: late-time acceleration and the hierarchy problem
• Observational signatures of f(R) dark energy models that satisfy cosmological and local gravity constraints
• Constraining f(R) Gravity as a Scalar Tensor Theory
• Solar system and equivalence principle constraints on f(R) gravity by chameleon approach
• Matter instability in modified gravity
• Non-singular exponential gravity: a simple theory for early- and late-time accelerated expansion
• Constraints on scalar-tensor models of dark energy from observational and local gravity tests
• Cosmological evolution in exponential gravity
• Oscillations of the F(R) dark energy in the accelerating universe
• Constraints from the CMB temperature and other common observational data-sets on variable dark energy density models
• Singularity problem in f(R) model with non-minimal coupling

Cited by in corpus (3)

• Constraining f(R) gravity in solar system, cosmology and binary pulsar systems
• Cosmological constraints on $R^2$-corrected Appleby-Battye model
• Exact inflationary solutions in exponential gravity