Large-Scale Structure in Brane-Induced Gravity I. Perturbation Theory
arXiv:0906.4545 · doi:10.1103/PhysRevD.80.104006
Abstract
We study the growth of subhorizon perturbations in brane-induced gravity using perturbation theory. We solve for the linear evolution of perturbations taking advantage of the symmetry under gauge transformations along the extra-dimension to decouple the bulk equations in the quasistatic approximation, which we argue may be a better approximation at large scales than thought before. We then study the nonlinearities in the bulk and brane equations, concentrating on the workings of the Vainshtein mechanism by which the theory becomes general relativity (GR) at small scales. We show that at the level of the power spectrum, to a good approximation, the effect of nonlinearities in the modified gravity sector may be absorbed into a renormalization of the gravitational constant. Since the relation between the lensing potential and density perturbations is entirely unaffected by the extra physics in these theories, the modified gravity can be described in this approximation by a single function, an effective gravitational constant for nonrelativistic motion that depends on space and time. We develop a resummation scheme to calculate it, and provide predictions for the nonlinear power spectrum. At the level of the large-scale bispectrum, the leading order corrections are obtained by standard perturbation theory techniques, and show that the suppression of the brane-bending mode leads to characteristic signatures in the non-Gaussianity generated by gravity, generic to models that become GR at small scales through second-derivative interactions. We compare the predictions in this work to numerical simulations in a companion paper.
36 pages, 10 figures. v2: corrected typos, misstatement, added clarifications, references. Submitted to PRD
References in corpus (37)
- Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
- Covariant Galileon
- Nonlinear Evolution of Baryon Acoustic Oscillations
- A Parameterized Post-Friedmann Framework for Modified Gravity
- Large Scale Structure as a Probe of Gravitational Slip
- Distinguishing Modified Gravity from Dark Energy
- Searching for modified growth patterns with tomographic surveys
- Degravitation of the Cosmological Constant and Graviton Width
- Observational Tests of Modified Gravity
- Equivalence Principle Implications of Modified Gravity Models
- Dark Energy versus Modified Gravity
- Non-linear evolution of f(R) cosmologies II: power spectrum
- Flowing with Time: a New Approach to Nonlinear Cosmological Perturbations
- Multi-Point Propagators in Cosmological Gravitational Instability
- Weak Lensing Probes of Modified Gravity
- Cascading DGP
- `Eppur Si Muove': On The Motion of the Acoustic Peak in the Correlation Function
- Non-linear structure formation and the acoustic scale
- Constraints on a New Post-General Relativity Cosmological Parameter
- Predictive Power of Strong Coupling in Theories with Large Distance Modified Gravity
- Next Generation Redshift Surveys and the Origin of Cosmic Acceleration
- N-Body Simulations of DGP and Degravitation Theories
- Non-linear interactions in a cosmological background in the DGP braneworld
- Is Modified Gravity Required by Observations? An Empirical Consistency Test of Dark Energy Models
- Consistency test of general relativity from large scale structure of the Universe
- Distance, Growth Factor, and Dark Energy Constraints from Photometric Baryon Acoustic Oscillation and Weak Lensing Measurements
- A sub-horizon framework for probing the relationship between the cosmological matter distribution and metric perturbations
- Schwarzschild solution in brane induced gravity
- Bigravity and Lorentz-violating Massive Gravity
- Cosmological perturbations in the DGP braneworld: numeric solution
- A Multi-Parameter Investigation of Gravitational Slip
- Cargese Lectures on Brane Induced Gravity
- Bubbles in the Self-Accelerating Universe
- Gauge invariant cosmological perturbation theory for braneworlds
- Probing the Largest Cosmological Scales with the CMB-Velocity Correlation
- Mass Screening in Modified Gravity
- Constraints on higher-dimensional gravity from the cosmic shear three-point correlation function