Can background cosmology hold the key for modified gravity tests?

Abstract

Modified gravity theories are a popular alternative to dark energy as a possible explanation for the observed accelerating cosmic expansion, and their cosmological tests are currently an active research field. Studies in recent years have been increasingly focused on testing these theories in the nonlinear regime, which is computationally demanding. Here we show that, under certain circumstances, a whole class of theories can be ruled out by using background cosmology alone. This is possible because certain classes of models (i) are fundamentally incapable of producing specific background expansion histories, and (ii) said histories are incompatible with local gravity tests. As an example, we demonstrate that a popular class of models, $f(R)$ gravity, would not be viable if observations suggest even a slight deviation of the background expansion history from that of the $\Lambda$CDM paradigm.

6 pages, 3 figures; accepted for publication in Phys. Rev. D

References in corpus (12)

• The Confrontation between General Relativity and Experiment
• Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
• Beyond the Cosmological Standard Model
• The Large Scale Structure of f(R) Gravity
• The Cosmology of f(R) Gravity in the Metric Variational Approach
• f(R) Gravity and Chameleon Theories
• N-body Simulations for f(R) Gravity using a Self-adaptive Particle-Mesh Code
• Non-linear evolution of f(R) cosmologies I: methodology
• Examining the evidence for dynamical dark energy
• Constraining $f(R)$ Gravity Theory Using Weak Lensing Peak Statistics from the Canada-France-Hawaii-Telescope Lensing Survey
• Hydrodynamic Effects in the Symmetron and $f(R)$-gravity Models
• On the Emergence of Accelerating Cosmic Expansion in f(R) Theories of Gravity

Cited by in corpus (3)

• Speeding up $N$-body simulations of modified gravity: Chameleon screening models
• Galaxy-galaxy weak gravitational lensing in $f(R)$ gravity
• Calculation of the critical overdensity in the spherical-collapse approximation