An effective theory of accelerated expansion

Abstract

We work out an effective theory of accelerated expansion to describe general phenomena of inflation and acceleration (dark energy) in the Universe. Our aim is to determine from theoretical grounds, in a physically-motivated and model independent way, which and how many (free) parameters are needed to broadly capture the physics of a theory describing cosmic acceleration. Our goal is to make as much as possible transparent the physical interpretation of the parameters describing the expansion. We show that, at leading order, there are five independent parameters, of which one can be constrained via general relativity tests. The other four parameters need to be determined by observing and measuring the cosmic expansion rate only, H(z). Therefore we suggest that future cosmology surveys focus on obtaining an accurate as possible measurement of $H(z)$ to constrain the nature of accelerated expansion (dark energy and/or inflation).

In press; minor changes, results unchanged

References in corpus (6)

• Dynamics of dark energy
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Dark Energy and the Accelerating Universe
• Reconstructing Dark Energy
• Effective Field Theory for Inflation
• Linearized f(R) Gravity: Gravitational Radiation & Solar System Tests

Cited by in corpus (14)

• Improved constraints on the expansion rate of the Universe up to z~1.1 from the spectroscopic evolution of cosmic chronometers
• Dark Energy or Modified Gravity? An Effective Field Theory Approach
• Effective Field Theory of Cosmic Acceleration: an implementation in CAMB
• Effective Field Theory of Cosmic Acceleration: constraining dark energy with CMB data
• Constraints on deviations from $\Lambda$CDM within Horndeski gravity
• An Extended action for the effective field theory of dark energy: a stability analysis and a complete guide to the mapping at the basis of EFTCAMB
• Testing Hu-Sawicki f(R) gravity with the Effective Field Theory approach
• Signatures of Horndeski gravity on the Dark Matter Bispectrum
• Effective Field Theory of Dark Energy: a Dynamical Analysis
• On the stability conditions for theories of modified gravity in presence of matter fields
• Cosmological Implications of the Effective Field Theory of Cosmic Acceleration
• The parameter space of Cubic Galileon models for cosmic acceleration
• Constraints on Dark Energy state equation with varying pivoting redshift
• Recovery of fluctuation spectrum evolution from tomographic shear spectra