Constraining the Nature of Dark Energy using the SKA

Abstract

We investigate the potential of the Square Kilometer Array Telescope (SKA) to constrain the sound speed of dark energy. The Integrated Sachs Wolfe (ISW) effect results in a significant power spectrum signal when CMB temperature anisotropies are cross-correlated with galaxies detectable with the SKA in HI. We consider using this measurement, the autocorrelation of HI galaxies and the CMB temperature power spectrum to derive constraints on the sound speed. We study the contributions to the cross-correlation signal made by galaxies at different redshifts and use redshift tomography to improve the signal-to-noise. We use a chi-square analysis to estimate the significance of detecting a sound speed different from that expected in quintessence models, finding that there is potential to distinguish very low sound speeds from the quintessence value.

arXiv comment8 pages, 8 figures; updated references for publication MNRAS

References in corpus (34)

• 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
• Quintessence, Cosmic Coincidence, and the Cosmological Constant
• A Dynamical Solution to the Problem of a Small Cosmological Constant and Late-time Cosmic Acceleration
• Coupled Quintessence
• Cosmological Perturbation Theory in the Synchronous vs. Conformal Newtonian Gauge
• Cosmological Perturbation Theory in the Synchronous and Conformal Newtonian Gauges
• The 3D power spectrum of galaxies from the SDSS
• An All-Sky Analysis of Polarization in the Microwave Background
• The 2dF Galaxy Redshift Survey: The power spectrum and the matter content of the universe
• Structure Formation with Generalized Dark Matter
• A correlation of the cosmic microwave sky with large scale structure
• Probing dark energy perturbations: the dark energy equation of state and speed of sound as measured by WMAP
• Large Scale Cosmic Microwave Background Anisotropies and Dark Energy
• Joint Galaxy-Lensing Observables and the Dark Energy
• The evolution of Omega(HI) and the epoch of formation of damped Lyman-alpha absorbers
• Cross-Correlation of the Cosmic Microwave Background with the 2MASS Galaxy Survey: Signatures of Dark Energy, Hot Gas, and Point Sources
• Dark Synergy: Gravitational Lensing and the CMB
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Dark Energy Induced Correlation with Radio Sources
• The 1000 Brightest HIPASS Galaxies: HI Mass Function and Omega_HI
• The Mass Power Spectrum in Quintessence Cosmological Models
• Measurement of the gravitational potential evolution from the cross-correlation between WMAP and the APM Galaxy survey
• Cross-correlation of WMAP 3rd year and the SDSS DR4 galaxy survey: new evidence for Dark Energy
• Constraining dark energy with cross-correlated CMB and Large Scale Structure data
• Integrated Sachs-Wolfe effect in Cross-Correlation: The Observer's Manual
• Measuring Dark Energy Clustering with CMB-Galaxy Correlations
• Constraints on the sound speed of dark energy
• Measuring $\alpha$ in the Early Universe: CMB Polarization, Reionization and the Fisher Matrix Analysis
• Tracking Dark Energy with the ISW effect: short and long-term predictions
• Probing dark energy with baryonic oscillations and future radio surveys of neutral Hydrogen
• The Weak Clustering of Gas-Rich Galaxies
• Hydrogen 21-Centimeter Emission from a Galaxy at Cosmological Distance
• Model-independent dark energy differentiation with the ISW effect

Cited by in corpus (19)

• The Effective Theory of Quintessence: the w<-1 Side Unveiled
• Cosmography and constraints on the equation of state of the Universe in various parametrizations
• Theoretical Models of Dark Energy
• Spherical collapse in quintessence models with zero speed of sound
• Dark energy with non-adiabatic sound speed: initial conditions and detectability
• Updated constraints on $f(\mathcal{R})$ gravity from cosmography
• Cosmological structure formation with clustering quintessence
• Variable sound speed in interacting dark energy models
• Stationary Configurations Imply Shift Symmetry: No Bondi Accretion for Quintessence / k-Essence
• High Redshift Standard Candles: Predicted Cosmological Constraints
• Non-linear dark energy clustering
• The nonlinear power spectrum in clustering quintessence cosmologies
• The effect of reionization on the CMB-density correlation
• Investigating clustering dark energy with 3d weak cosmic shear
• Nonlinear effects of dark energy clustering beyond the acoustic scales
• The CMBR ISW and HI 21-cm Cross-correlation Angular Power Spectrum
• Covariance of dark energy parameters and sound speed constraints from large HI surveys
• Accurate relativistic observables from post-processing light cone catalogues
• A varying Dark Energy effective speed of sound parameter in the phantom Universe