Nonlinear modulation of the HI power spectrum on ultra-large scales. I

Abstract

Intensity mapping of the neutral hydrogen brightness temperature promises to provide a three-dimensional view of the universe on very large scales. Nonlinear effects are typically thought to alter only the small-scale power, but we show how they may bias the extraction of cosmological information contained in the power spectrum on ultra-large scales. For linear perturbations to remain valid on large scales, we need to renormalize perturbations at higher order. In the case of intensity mapping, the second-order contribution to clustering from weak lensing dominates the nonlinear contribution at high redshift. Renormalization modifies the mean brightness temperature and therefore the evolution bias. It also introduces a term that mimics white noise. These effects may influence forecasting analysis on ultra-large scales.

13 pages, 6 figures. Argument made that 3rd order terms are subdominant; clarification of various subtleties; minor corrections; Comment on EoR, typos corrected, matches published version

References in corpus (13)

• Clustering of dark matter tracers: generalizing bias for the coming era of precision LSS
• Late-time cosmology with 21cm intensity mapping experiments
• A critical look at cosmological perturbation theory techniques
• Testing General Relativity with 21 cm intensity mapping
• Ultra large-scale cosmology in next-generation experiments with single tracers
• Constraining ultra large-scale cosmology with multiple tracers in optical and radio surveys
• Beyond the Linear-Order Relativistic Effect in Galaxy Clustering: Second-Order Gauge-Invariant Formalism
• Hunting down horizon-scale effects with multi-wavelength surveys
• Galaxy number counts to second order and their bispectrum
• Perturbation Theory Reloaded II: Non-linear Bias, Baryon Acoustic Oscillations and Millennium Simulation In Real Space
• Observational signatures of modified gravity on ultra-large scales
• Halo Sampling, Local Bias and Loop Corrections
• Effects of biasing on the galaxy power spectrum at large scales

Cited by in corpus (19)

• Line-Intensity Mapping: 2017 Status Report
• The bispectrum of relativistic galaxy number counts
• The Full-Sky Angular Bispectrum in Redshift Space
• The dipole of the galaxy bispectrum
• Detecting the relativistic bispectrum in 21cm intensity maps
• Local primordial non-Gaussianity in the relativistic galaxy bispectrum
• Redshift space distortions of the {\rm HI} 21-cm intensity mapping signal due to the internal motions within galaxies
• Full-sky bispectrum in redshift space for 21cm intensity maps
• Multipoles of the relativistic galaxy bispectrum
• Modelling the post-reionization neutral hydrogen ($\mathrm{HI}$) 21-cm bispectrum
• Optimal computation of anisotropic galaxy three point correlation function multipoles using 2DFFTLOG formalism
• The Breakdown Scale of HI Bias Linearity
• Intensity mapping of the 21cm emission: lensing
• Imprint of non-linear effects on HI intensity mapping on large scales
• Testing the equivalence principle on cosmological scales using the odd multipoles of galaxy cross-power spectrum and bispectrum
• The galaxy bias at second order in general relativity with Non-Gaussian initial conditions
• Apparent parity violation in the observed galaxy trispectrum
• The effect of finite halo size on the clustering of neutral hydrogen
• Lensing contribution to the 21cm intensity bispectrum