Nonlocal gravity and the diffusion equation
arXiv:1004.5144 · doi:10.1103/PhysRevD.82.123518
Abstract
We propose a nonlocal scalar-tensor model of gravity with pseudodifferential operators inspired by the effective action of p-adic string and string field theory on flat spacetime. An infinite number of derivatives act both on the metric and scalar field sector. The system is localized via the diffusion equation approach and its cosmology is studied. We find several exact dynamical solutions, also in the presence of a barotropic fluid, which are stationary in the diffusion flow. In particular, and contrary to standard general relativity, there exist solutions with exponential and power-law scale factor also in an open universe, as well as solutions with sudden future singularities or a bounce. Also, from the point of view of quantum field theory, spontaneous symmetry breaking can be naturally realized in the class of actions we consider.
18 pages, 5 figures. v2: typos corrected, references added. Major changes are an expansion of the discussion of homogeneous perturbations and the inclusion of cosmological fluids in the dynamics
References in corpus (33)
- Class of viable modified gravities describing inflation and the onset of accelerated expansion
- Modified non-local-F(R) gravity as the key for the inflation and dark energy
- Dynamics of Nonlocal Cosmology
- Accelerating cosmologies from non-local higher-derivative gravity
- Phantom and non-phantom dark energy: The cosmological relevance of non-locally corrected gravity
- Localization of nonlocal theories
- Dynamics with Infinitely Many Derivatives: The Initial Value Problem
- Route to nonlocal cosmology
- Reconstructing the Distortion Function for Nonlocal Cosmology
- Newtonian limit of nonlocal cosmology
- Ghost conditions for Gauss-Bonnet cosmologies
- Trace Anomaly in Quantum Spacetime Manifold
- Bouncing and Accelerating Solutions in Nonlocal Stringy Models
- Large Nongaussianity from Nonlocal Inflation
- Dynamics in Nonlocal Cosmological Models Derived from String Field Theory
- Fading Gravity and Self-Inflation
- Nonlinear equations for p-adic open, closed, and open-closed strings
- Diffusing non-local inflation: Solving the field equations as an initial value problem
- One-loop effective action for non-local modified Gauss-Bonnet gravity in de Sitter space
- On the Null Energy Condition and Cosmology
- Stretching the Inflaton Potential with Kinetic Energy
- Quantization of the Riemann Zeta-Function and Cosmology
- Tachyon solutions in boundary and cubic string field theory
- Nonlocal instantons and solitons in string models
- Dynamics with Infinitely Many Derivatives: Variable Coefficient Equations
- Kinks of open superstring field theory
- Cosmological Signature of Tachyon Condensation
- Closed Bosonic String Field Theory at Quintic Order II: Marginal Deformations and Effective Potential
- Dynamics and Stability of Light-Like Tachyon Condensation
- Stability of multi-field cosmological solutions
- Cosmology of the closed string tachyon
- Field Redefinitions, T-duality and Solutions in Closed String Field Theories
- Rolling Solution for Tachyon Condensation in Open String Field Theory