Matter may matter

Abstract

We propose a gravitational theory in which the effective Lagrangian of the gravitational field is given by an arbitrary function of the Ricci scalar, the trace of the matter energy-momentum tensor, and the contraction of the Ricci tensor with the matter energy-momentum tensor. The matter energy-momentum tensor is generally not conserved, thus leading to the appearance of an extra-force, acting on massive particles in a gravitational field. The stability conditions of the theory with respect to local perturbations are also obtained. The cosmological implications of the theory are investigated, representing an exponential solution. Hence a Ricci tensor - energy-momentum tensor coupling may explain the recent acceleration of the Universe, without resorting to the mysterious dark energy.

Received an "Honorable Mention" in the Gravity Research Foundation Essay Contest 2014

References in corpus (21)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• A Large Mass Hierarchy from a Small Extra Dimension
• An Alternative to Compactification
• Dynamics of dark energy
• f(R) Theories Of Gravity
• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Type Ia Supernova Discoveries at z>1 From the Hubble Space Telescope: Evidence for Past Deceleration and Constraints on Dark Energy Evolution
• Modified Gravity and Cosmology
• f(R) theories
• f(R,T) gravity
• Extra force in $f(R)$ modified theories of gravity
• Brane-world gravity
• Can modified gravity explain accelerated cosmic expansion?
• f(R,L_m) gravity
• f(R, T, R_μνT^μν) gravity phenomenology and ΛCDM universe
• Further matters in space-time geometry: $f(R,T,R_{\mu \nu }{T}^{\mu \nu })$ gravity
• Born-Infeld-Einstein Actions?
• Modified gravity with arbitrary coupling between matter and geometry
• Galactic Searches for Dark Matter
• Dark matter as a geometric effect in f(R) gravity

Cited by in corpus (13)

• Generalized curvature-matter couplings in modified gravity
• Mimetic gravity: a review of recent developments and applications to cosmology and astrophysics
• Palatini formulation of $f(R,T)$ gravity theory, and its cosmological implications
• Generalizing the coupling between geometry and matter: $f(R,L_m,T)$ gravity
• Cosmic acceleration in dust only Universe via energy-momentum powered gravity
• Quantum Cosmology of $f(R,T)$ gravity
• Influence of Modification of Gravity on the Complexity Factor of Static Spherical Structures
• Cosmological implications of modified gravity induced by quantum metric fluctuations
• Cosmic Acceleration From Matter-Curvature Coupling
• Late-time cosmological evolution of a general class of f(R, T) gravity with minimal curvature-matter coupling
• Cosmic Acceleration and Geodesic Deviation in Chameleon Scalar Field Model
• Non-Singular Collapse Scenario From Matter-Curvature Coupling
• Cosmological Solutions of Chameleon Scalar Field Model