Effectively nonlocal metric-affine gravity
arXiv:1509.06552 · doi:10.1103/PhysRevD.93.064081
Abstract
In metric-affine theories of gravity such as the C-theories, the spacetime connection is associated to a metric that is nontrivially related to the physical metric. In this article, such theories are rewritten in terms of a single metric and it is shown that they can be recast as effectively nonlocal gravity. With some assumptions, known ghost-free theories with non-singular and cosmologically interesting properties may be recovered. Relations between different formulations are analysed at both perturbative and nonperturbative levels taking carefully into account subtleties with boundary conditions in the presence of integral operators in the action, and equivalences between theories related by nonlocal redefinitions of the fields are verified at the level of equations of motion. This suggests a possible geometrical interpretation of nonlocal gravity as an emergent property of non-Riemannian spacetime structure.
12 pages; minor changes; published version
References in corpus (15)
- Palatini Approach to Modified Gravity: f(R) Theories and Beyond
- Towards a Resolution of the Cosmological Singularity in Non-local Higher Derivative Theories of Gravity
- Dynamics of Nonlocal Cosmology
- Mass-gap for black hole formation in higher derivative and ghost free gravity
- Cosmology of hybrid metric-Palatini f(X)-gravity
- Nonlocal Gravity Simulates Dark Matter
- Generalised Quadratic Curvature, Non-Local Infrared Modifications of Gravity and Newtonian Potentials
- Unifying Einstein and Palatini gravities
- On new variational principles as alternatives to the Palatini method
- Aspects of Nonlocality in Quantum Field Theory, Quantum Gravity and Cosmology
- Field equations and cosmology for a class of nonlocal metric models of MOND
- ADM Analysis of Gravity Models within the Framework of Bimetric Variational Formalism
- Extended Weyl Invariance in a Bimetric Model and Partial Masslessness
- Some Cosmological Solutions of a Nonlocal Modified Gravity
- Non-local formulation of ghost-free bigravity theory