A practical approach to cosmological perturbations in modified gravity

Abstract

The next generation of large scale surveys will not only measure cosmological parameters within the framework of General Relativity, but will also allow for precision tests of the framework itself. At the order of linear perturbations, departures from the growth in the LCDM model can be quantified in terms of two functions of time and Fourier number k. We argue that in local theories of gravity, in the quasi-static approximation, these functions must be ratios of polynomials in k, with the numerator of one function being equal to the denominator of the other. Moreover, the polynomials are even and of second degree in practically all viable models considered today. This means that, without significant loss of generality, one can use data to constraint only five functions of a single variable, instead of two functions of two variables. Furthermore, since the five functions are expected to be slowly varying, one can fit them to data in a non-parametric way with the aid of an explicit smoothness prior. We discuss practical application of this parametrization to forecasts and fits.

9 pages, v2: matching the published version

References in corpus (50)

• Efficient Computation of CMB anisotropies in closed FRW models
• f(R) theories
• 4D Gravity on a Brane in 5D Minkowski Space
• Is Cosmic Speed-Up Due to New Gravitational Physics?
• The galileon as a local modification of gravity
• Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
• Chameleon Fields: Awaiting Surprises for Tests of Gravity in Space
• Disappearing cosmological constant in f(R) gravity
• The linear power spectrum of observed source number counts
• The Effective Field Theory of Dark Energy
• What galaxy surveys really measure
• A Parameterized Post-Friedmann Framework for Modified Gravity
• Parameterized Beyond-Einstein Growth
• A discriminating probe of gravity at cosmological scales
• Measuring primordial non-gaussianity without cosmic variance
• Large Scale Structure as a Probe of Gravitational Slip
• New Perspective on Galaxy Clustering as a Cosmological Probe: General Relativistic Effects
• The pattern of growth in viable f(R) cosmologies
• Parameterization of Dark-Energy Properties: a Principal-Component Approach
• Distinguishing Modified Gravity from Dark Energy
• Large-scale clustering of galaxies in general relativity
• Searching for modified growth patterns with tomographic surveys
• General Relativistic Description of the Observed Galaxy Power Spectrum: Do We Understand What We Measure?
• Effective gravitational couplings for cosmological perturbations in the most general scalar-tensor theories with second-order field equations
• Testing gravity with CAMB and CosmoMC
• A Unified Description of Screened Modified Gravity
• Current constraints on the cosmic growth history
• Testing General Relativity with Current Cosmological Data
• The Parameterized Post-Friedmann Framework for Theories of Modified Gravity: Concepts, Formalism and Examples
• Testing General Relativity with 21 cm intensity mapping
• How to optimally parametrize deviations from General Relativity in the evolution of cosmological perturbations
• Observables and unobservables in dark energy cosmologies
• Testing General Relativity on Horizon Scales and the Primordial non-Gaussianity
• Going beyond the Kaiser redshift-space distortion formula: a full general relativistic account of the effects and their detectability in galaxy clustering
• How to suppress the shot noise in galaxy surveys
• Disentangling non-Gaussianity, bias and GR effects in the galaxy distribution
• Examining the evidence for dynamical dark energy
• Cosmological Tests of General Relativity with Future Tomographic Surveys
• Effective action approach to cosmological perturbations in dark energy and modified gravity
• Towards a fully consistent parameterization of modified gravity
• Fables of reconstruction: controlling bias in the dark energy equation of state
• Investigating dark energy experiments with principal components
• Cosmological tests of General Relativity: a principal component analysis
• Testing General Relativity at Cosmological Scales: Implementation and Parameter Correlations
• Modified Gravity Tomography
• Theoretical Priors On Modified Growth Parametrisations
• Consistent perturbations in an imperfect fluid
• Consistent cosmological modifications to the Einstein equations
• Practical solutions for perturbed f(R) gravity
• Linear growth of matter density perturbations in f(R,G) theories

Cited by in corpus (123)

• Testing General Relativity with Present and Future Astrophysical Observations
• Beyond the Cosmological Standard Model
• Cosmology and Fundamental Physics with the Euclid Satellite
• Cosmology and fundamental physics with the Euclid satellite
• Cosmological Tests of Modified Gravity
• Beyond $\Lambda$CDM: Problems, solutions, and the road ahead
• Dark Energy vs. Modified Gravity
• Testing General Relativity in Cosmology
• Maximal freedom at minimum cost: linear large-scale structure in general modifications of gravity
• Essential Building Blocks of Dark Energy
• Dark Energy Survey Year 1 Results: Constraints on Extended Cosmological Models from Galaxy Clustering and Weak Lensing
• Dark energy two decades after: Observables, probes, consistency tests
• Core Cosmology Library: Precision Cosmological Predictions for LSST
• Dark energy in Horndeski theories after GW170817: A review
• Dark Energy in light of Multi-Messenger Gravitational-Wave astronomy
• Effective Field Theory of Cosmic Acceleration: constraining dark energy with CMB data
• Probing the theory of gravity with gravitational lensing of gravitational waves and galaxy surveys
• Structure formation in $f(T)$ gravity and a solution for $H_0$ tension
• Effective Field Theory of Cosmological Perturbations
• Limits of Quasi-Static Approximation in Modified-Gravity Cosmologies
• Growth of Cosmic Structure: Probing Dark Energy Beyond Expansion
• A Simplified Approach to General Scalar-Tensor Theories
• What can Cosmology tell us about Gravity? Constraining Horndeski with Sigma and Mu
• Relativistic scalar fields and the quasi-static approximation in theories of modified gravity
• Extending cosmological tests of General Relativity with the Square Kilometre Array
• A designer approach to $f(Q)$ gravity and cosmological implications
• Unraveling the effective fluid approach for $f(R)$ models in the subhorizon approximation
• Multi-messenger tests of gravity with weakly lensed gravitational waves
• MGCAMB with massive neutrinos and dynamical dark energy
• Large-scale structure phenomenology of viable Horndeski theories
• Phenomenology of the generalized cubic covariant Galileon model and cosmological bounds
• Phenomenology of dark energy: exploring the space of theories with future redshift surveys
• KiDS+2dFLenS+GAMA: Testing the cosmological model with the $E_{\mathrm{G}}$ statistic
• Probing modified gravity theories and cosmology using gravitational-waves and associated electromagnetic counterparts
• Banana Split: Testing the Dark Energy Consistency with Geometry and Growth
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: constraining modified gravity
• A general theory of linear cosmological perturbations: scalar-tensor and vector-tensor theories
• The road ahead of Horndeski: cosmology of surviving scalar-tensor theories
• Probing Dark Energy through Scale Dependence
• Searching for Modified Gravity: Scale and Redshift Dependent Constraints from Galaxy Peculiar Velocities
• Challenges in Connecting Modified Gravity Theory and Observations
• Horava Gravity in the Effective Field Theory formalism: from cosmology to observational constraints
• Observational signatures of modified gravity on ultra-large scales
• New Gravitational Scales in Cosmological Surveys
• Modified Gravity Constraints from the Full Shape Modeling of Clustering Measurements from DESI 2024
• Testing deviations from $\Lambda$CDM with growth rate measurements from 6 Large Scale Structure Surveys at $\mathbf{z}=0.06$ to 1
• Growth of Cosmic Structure
• Phenomenology of Large Scale Structure in scalar-tensor theories: joint prior covariance of $w_{\text{DE}}$, $\Sigma$ and $\mu$ in Horndeski
• Possibility of realizing weak gravity in redshift space distortion measurements
• Effective Field Theory of Dark Energy: a Dynamical Analysis
• An effective description of dark matter and dark energy in the mildly non-linear regime
• A parametrisation of modified gravity on nonlinear cosmological scales
• A Fast Route to Modified Gravitational Growth
• Principal reconstructed modes of dark energy and gravity
• $N$-body simulations for parametrised modified gravity
• Observational signatures of the theories beyond Horndeski
• Parameterizing dark sector perturbations via equations of state
• Fast and accurate predictions of the nonlinear matter power spectrum for general models of Dark Energy and Modified Gravity
• Cosmological Constraints on sub-horizon scales modified gravity theories with MGCLASS II
• Searching for scalar gravitational interactions in current and future cosmological data
• Exploring degeneracies in modified gravity with weak lensing
• Testing gravity with $E_G$: mapping theory onto observations
• Absorption by black hole remnants in metric-affine gravity
• New MGCAMB tests of gravity with CosmoMC and Cobaya
• Beyond lensing by the cosmological constant
• The Parametrized Post-Newtonian-Vainshteinian Formalism
• Constraints on massive vector dark energy models from integrated Sachs-Wolfe-galaxy cross-correlations
• $f(Q)$-gravity and neutrino physics
• Assessing the impact of bulk and shear viscosities on large scale structure formation
• Nonlinear evolution of initially biased tracers in modified gravity
• New cosmological constraints on $f(T)$ gravity in light of full Planck-CMB and type Ia supernovae data
• J-PAS: forecasts on dark energy and modified gravity theories
• Comparison of different approaches to the quasi-static approximation in Horndeski models
• $\text{Hi-COLA}$: Fast, approximate simulations of structure formation in Horndeski gravity
• Gravitational Redshift Constraints on the Effective Theory of Interacting Dark Energy
• Current constraints on deviations from General Relativity using binning in redshift and scale
• Probing Modified Gravity with Integrated Sachs-Wolfe CMB and Galaxy Cross-correlations
• Cosmological gravity on all scales: simple equations, required conditions, and a framework for modified gravity
• Observable physical modes of modified gravity
• A cosmological exclusion plot: Towards model-independent constraints on modified gravity from current and future growth rate data
• How can we tell whether dark energy is composed by multiple fields?
• New scaling solutions in cubic Horndeski theories
• Sweeping Horndeski Canvas: New Growth-Rate Parameterization for Modified-Gravity Theories
• Gravity in mimetic scalar-tensor theories after GW170817
• The effective field theory of K-mouflage
• Euclid: Constraining linearly scale-independent modifications of gravity with the spectroscopic and photometric primary probes
• Marked correlation functions in perturbation theory
• Parametrizations for tests of gravity
• Model-independent constraints on modified gravity from current data and from the Euclid and SKA future surveys
• Gravitational Waves: A Test for Modified Gravity
• Constraining gravity with a new precision $E_G$ estimator using Planck + SDSS BOSS
• Initial conditions for cosmological N-body simulations of the scalar sector of theories of Newtonian, Relativistic and Modified Gravity
• Non-minimally coupled gravity constraints from DESI DR2 data
• Constraining dark sector perturbations I: cosmic shear and CMB lensing
• Euclid preparation. Modelling spectroscopic clustering on mildly nonlinear scales in beyond-$\Lambda$CDM models
• Cosmological study of a symmetric teleparallel gravity model
• Dark sector evolution in Horndeski models
• The Parameterized Post-Newtonian-Vainshteinian formalism for the Galileon field
• Cosmological applications of the Brown-York quasilocal mass
• Cosmological Tests of Gravity: A Future Perspective
• Data-driven and Almost Model-independent Reconstruction of Modified Gravity
• The Effective Fluid approach for Modified Gravity and its applications
• Simple numerical implementation of general dark energy models
• Parametrizing growth in dark energy and modified gravity models
• Tracking the validity of the quasi-static and sub-horizon approximations in modified gravity
• Constraining cosmological scaling solutions of a Galileon field
• The Fisher gAlaxy suRvey cOde ($\text{FARO}$)
• Testing $f(T)$ Gravity with Cosmological Observations: Confronting the Hubble Tension and Implications for the Late-Time Universe
• Modified Gravity at Astrophysical Scales
• Cosmic Growth Signatures of Modified Gravitational Strength
• Parametrizing modified gravities with vector degrees of freedom: anisotropic growth and lensing
• Modified gravity versus shear viscosity: imprints on the scalar matter perturbations
• Non-linear density-velocity dynamics in $f(R)$ gravity from spherical collapse
• Measuring the growth of structure by matching dark matter haloes to galaxies with VIPERS and SDSS
• Constraining Scale Dependent Growth with Redshift Surveys
• Testing for gravitational preferred directions with galaxy and lensing surveys
• Principal Components for Model-Agnostic Modified Gravity with 3x2pt
• Minimal parameterizations for modified gravity
• Fullshape power spectrum for the Symmetron modified gravity model
• Geometry vs growth: Internal consistency of the flat ΛCDM model with KiDS-1000
• Matter growth in extended $\Lambda$CDM cosmology
• Cosmology with the Roman Space Telescope -- Synergies with CMB lensing
• Toward testing gravity with LSST using $E_G$