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arXiv · 1403.2076

Hemispherical Power Asymmetry from a Space-Dependent Component of the Adiabatic Power Spectrum

John McDonald
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Abstract

The hemispherical power asymmetry observed by Planck and WMAP can be interpreted as due to a spatially-varying and scale-dependent component of the adiabatic power spectrum. We derive general constraints on the magnitude and scale-dependence of a component with a dipole spatial variation. The spectral index and the running of the spectral index can be significantly shifted from their inflation model values, resulting in a smaller spectral index and a more positive running. A key prediction is a hemispherical asymmetry of the spectral index and of its running. Measurement of these asymmetries can test the structure of the perturbation responsible for the CMB power asymmetry.

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John McDonald. 2014-06-17. Hemispherical Power Asymmetry from a Space-Dependent Component of the Adiabatic Power Spectrum. https://doi.org/10.1103/physrevd.89.127303

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