Late-time constraints on modified Gauss-Bonnet cosmology

Abstract

In this paper, we consider a gravitational action containing a combination of the Ricci scalar, $R$, and the topological Gauss--Bonnet term, $G$. Specifically, we study the cosmological features of a particular class of modified gravity theories selected by symmetry considerations, namely the $f(R,G)=R^n{G}^{1-n}$ model. In the context of a spatially flat, homogeneous and isotropic background, we show that the currently observed acceleration of the Universe can be addressed through geometry, hence avoiding \emph{de facto} the shortcomings of the cosmological constant. We thus present a strategy to numerically solve the Friedmann equations in presence of pressureless matter and obtain the redshift behavior of the Hubble expansion rate. Then, to check the viability of the model, we place constraints on the free parameters of the theory by means of a Bayesian Monte Carlo method applied to late-time cosmic observations. Our results show that the $f(R,G)$ model is capable of mimicking the low-redshift behavior of the standard $\Lambda$CDM model, though substantial differences emerge when going toward high redshifts, leading to the absence of a standard matter-dominated epoch. Finally, we investigate the energy conditions and show that, under suitable choices for the values of the cosmographic parameters, they are all violated when considering the mean value of $n$ obtained from our analysis, as occurs in the case of a dark fluid.

11 pages, 3 figures, 1 table. Accepted for publication in General Relativity and Gravitation

References in corpus (25)

• Dynamics of dark energy
• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Disappearing cosmological constant in f(R) gravity
• Beyond the Cosmological Standard Model
• Are f(R) dark energy models cosmologically viable ?
• Extended Gravity Cosmography
• The Cosmology of Modified Gauss-Bonnet Gravity
• Cosmological inflation in $F(R,\mathcal{G})$ gravity
• Matter instability in modified gravity
• Generalized energy conditions in Extended Theories of Gravity
• Holographic dark energy from nonadditive entropy: cosmological perturbations and observational constraints
• Physically viable solutions of anisotropic spheres in $f(\mathcal{R},\mathcal{G})$ gravity satisfying the Karmarkar condition
• Density perturbations in general modified gravitational theories
• Noether Symmetry Approach in Gauss-Bonnet Cosmology
• Stability of Schwarzschild-like solutions in f(R,G) gravity models
• A Refined Einstein-Gauss-Bonnet Inflationary Theoretical Framework
• Vacuum structure for scalar cosmological perturbations in Modified Gravity Models
• Healing the cosmological constant problem during inflation through a unified quasi-quintessence matter field
• Unification of a Bounce with a Viable Dark Energy Era in Gauss-Bonnet Gravity
• Forecasting constraints on deviations from general relativity in $f(Q)$ gravity with standard sirens
• Extended logotropic fluids as unified dark energy models
• Cosmological entropy and generalized second law of thermodynamics in $F(R,G)$ theory of gravity
• Bottom-Up Reconstruction of Viable GW170817 Compatible Einstein-Gauss-Bonnet Theories
• Tracing the cosmic history by Gauss-Bonnet gravity
• Exact spherically symmetric solutions in modified Gauss-Bonnet gravity from Noether symmetry approach

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• Parity violation in gravitational waves and observational bounds from third-generation detectors
• Exploring departures from Schwarzschild black hole in $f(R)$ gravity
• Geometric and topological corrections to Schwarzschild black hole
• The Gauss-Bonnet topological scalar in the Geometric Trinity of Gravity
• The Noether Symmetry Approach: Foundation and applications. The case of scalar-tensor Gauss-Bonnet gravity
• A generalized $\Lambda$CDM model with parameterized Hubble parameter in particle creation, viscous and $f(R)$ model framework
• Teleparallel dark energy in a nonflat universe
• Can the NANOGrav observations constrain the geometry of the universe?
• Cosmological Solutions of Chameleon Scalar Field Model
• Dynamical Systems Analysis of $f(R,L_m)$ Gravity Model
• Constraints on cosmological parameters and CMB first acoustic peak in conformal Killing gravity