Fingerprinting Dark Energy II: weak lensing and galaxy clustering tests

Abstract

The characterization of dark energy is a central task of cosmology. To go beyond a cosmological constant, we need to introduce at least an equation of state and a sound speed and consider observational tests that involve perturbations. If dark energy is not completely homogeneous on observable scales then the Poisson equation is modified and dark matter clustering is directly affected. One can then search for observational effects of dark energy clustering using dark matter as a probe. In this paper we exploit an analytical approximate solution of the perturbation equations in a general dark energy cosmology to analyze the performance of next-decade large scale surveys in constraining equation of state and sound speed. We find that tomographic weak lensing and galaxy redshift surveys can constrain the sound speed of the dark energy only if the latter is small, of the order of $c_s\lesssim 0.01$ (in units of $c$). For larger sound speeds the error grows to 100% and more. We conclude that large scale structure observations contain very little information about the perturbations in canonical scalar field models with a sound speed of unity. Nevertheless, they are able to detect the presence of "cold" dark energy, i.e. a dark energy with non-relativistic speed of sound.

References in corpus (29)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Efficient Computation of CMB anisotropies in closed FRW models
• Cosmological Imprint of an Energy Component with General Equation of State
• Stable clustering, the halo model and nonlinear cosmological power spectra
• Power Spectra for Cold Dark Matter and its Variants
• Probing Dark Energy with Baryonic Acoustic Oscillations from Future Large Galaxy Redshift Surveys
• A Parameterized Post-Friedmann Framework for Modified Gravity
• Measuring the dark side (with weak lensing)
• Probing dark energy perturbations: the dark energy equation of state and speed of sound as measured by WMAP
• Probing Newton's Constant on Vast Scales: DGP Gravity, Cosmic Acceleration and Large Scale Structure
• Large Scale Cosmic Microwave Background Anisotropies and Dark Energy
• Structure formation in the DGP cosmological model
• Dark Energy versus Modified Gravity
• Measuring the Speed of Sound of Quintessence
• Measuring the effective complexity of cosmological models
• The dark degeneracy: On the number and nature of dark components
• Spherical collapse in quintessence models with zero speed of sound
• Crossing the Phantom Divide
• Measuring the Speed of Dark: Detecting Dark Energy Perturbations
• Constraints on perfect fluid and scalar field dark energy models from future redshift surveys
• Fingerprinting dark energy
• Streaming velocities as a dynamical estimator of Omega
• Bayesian Calibrated Significance Levels Applied to the Spectral Tilt and Hemispherical Asymmetry
• Model selection as a science driver for dark energy surveys
• Weak lensing in generalized gravity theories
• Unified dark energy and dark matter from a scalar field different from quintessence
• DUNE: The Dark Universe Explorer
• A dark energy view of inflation

Cited by in corpus (33)

• Cosmology and Fundamental Physics with the Euclid Satellite
• Cosmology and fundamental physics with the Euclid satellite
• Dark Matter and Dark Energy Interactions: Theoretical Challenges, Cosmological Implications and Observational Signatures
• The Intrinsic Alignment of Galaxies and its Impact on Weak Gravitational Lensing in an Era of Precision Cosmology
• Speeding up the universe using dust with pressure
• The phenomenological approach to modeling the dark energy
• A parametrization of the growth index of matter perturbations in various Dark Energy models and observational prospects using a Euclid-like survey
• Dark Energy in Practice
• Cosmological structure formation with clustering quintessence
• Consistent perturbations in an imperfect fluid
• Using dark energy to suppress power at small scales
• Fingerprinting Dark Energy III: distinctive marks of viscosity
• Accuracy of the growth index in the presence of dark energy perturbations
• Testing for dynamical dark energy models with redshift-space distortions
• Zero-point quantum fluctuations in cosmology
• Nonlinear cosmological consistency relations and effective matter stresses
• Full Investigation on the Dynamics of Power-Law Kinetic Quintessence
• Can dark energy viscosity be detected with the Euclid survey?
• Non-linear dark energy clustering
• A novel null test for the $\Lambda$CDM model with growth-rate data
• Sound speed of scalar field dark energy: weak effects and large uncertainties
• A short review on clustering dark energy
• The growth index of matter perturbations using the clustering of dark energy
• The nonlinear power spectrum in clustering quintessence cosmologies
• Discrimination between Lambda-CDM, quintessence, and modified gravity models using wide area surveys
• Combined constraints on deviations of dark energy from an ideal fluid from Euclid and Planck
• Evidence for dark matter modulation in CoGeNT?
• Cluster Probes of Dark Energy Clustering
• Investigating clustering dark energy with 3d weak cosmic shear
• Nonlinear effects of dark energy clustering beyond the acoustic scales
• Reconstruction of the null-test for the matter density perturbations
• Dark energy homogeneity in general relativity: Are we applying it correctly?
• Kerr-Newman black hole lensing of relativistic massive particles in the weak field limit