Evidence for horizon-scale power from CMB polarization

Abstract

The CMB temperature power spectrum offers ambiguous evidence for the existence of horizon-scale power in the primordial power spectrum due to uncertainties in spatial curvature and the physics of cosmic acceleration as well as the observed low quadrupole. Current polarization data from WMAP provide evidence for horizon-scale power that is robust to these uncertainties. Polarization on the largest scales arises mainly from scattering at z<6 when the universe is fully ionized, making the evidence robust to ionization history variations at higher redshifts as well. A cutoff in the power spectrum is limited to C=k_C/10^{-4} Mpc^{-1}<5.2 (95% CL) by polarization, only slightly weaker than joint temperature and polarization constraints in flat LCDM (C<4.2). Planck should improve the polarization limit to C<3.6 for any model of the acceleration epoch and ionization history as well as provide tests for foreground and systematic contamination.

4 pages, 2 figures; submitted to Phys. Rev. D (Rapid Communications). Code for modified reionization in CAMB and CosmoMC available at http://background.uchicago.edu/camb_rpc/

References in corpus (34)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Efficient Computation of CMB anisotropies in closed FRW models
• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results
• Cosmological parameters from CMB and other data: a Monte-Carlo approach
• 4D Gravity on a Brane in 5D Minkowski Space
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Likelihoods and Parameters from the WMAP data
• 4-Year COBE DMR Cosmic Microwave Background Observations: Maps and Basic Results
• Structure Formation with Generalized Dark Matter
• Suppressing the lower Multipoles in the CMB Anisotropies
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Angular Power Spectra
• Probing dark energy perturbations: the dark energy equation of state and speed of sound as measured by WMAP
• Reconstructing the primordial power spectrum
• Is the Low CMB Quadrupole a Signature of Spatial Curvature?
• Suppressing CMB Quadrupole with a Bounce from Contracting Phase to Inflation
• Does the small CMB quadrupole moment suggest new physics?
• Challenges to the DGP Model from Horizon-Scale Growth and Geometry
• A Low CMB Quadrupole from Dark Energy Isocurvature Perturbations
• Punctuated inflation and the low CMB multipoles
• Double Inflation and the Low CMB Quadrupole
• Can we have inflation with Omega > 1?
• Model-Independent Reionization Observables in the CMB
• Model-independent constraints on reionization from large-scale CMB polarization
• Closed Universes, de Sitter Space and Inflation
• A Bayesian analysis of the primordial power spectrum
• CMB quadrupole suppression: II. The early fast roll stage
• Post-WMAP Assessment of Infrared Cutoff in the Primordial Spectrum from Inflation
• An Infrared Cutoff Revealed by the Two Years of COBE-DMR Observations of Cosmic Temperature Fluctuations
• WMAP 3-year primordial power spectrum
• Large-scale power in the CMB and new physics: an analysis using Bayesian model comparison
• Reionization constraints from five-year WMAP data
• The CMB Quadrupole in a Polarized Light
• Can Cosmic Shear Shed Light on Low Cosmic Microwave Background Multipoles?

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