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arXiv · 0808.1570

Superhorizon Perturbations and the Cosmic Microwave Background

Adrienne L. Erickcek·Sean M. Carroll·Marc Kamionkowski
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Abstract

Superhorizon perturbations induce large-scale temperature anisotropies in the cosmic microwave background (CMB) via the Grishchuk-Zel'dovich effect. We analyze the CMB temperature anisotropies generated by a single-mode adiabatic superhorizon perturbation. We show that an adiabatic superhorizon perturbation in a LCDM universe does not generate a CMB temperature dipole, and we derive constraints to the amplitude and wavelength of a superhorizon potential perturbation from measurements of the CMB quadrupole and octupole. We also consider constraints to a superhorizon fluctuation in the curvaton field, which was recently proposed as a source of the hemispherical power asymmetry in the CMB.

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Adrienne L. Erickcek, Sean M. Carroll, Marc Kamionkowski. 2008-08-11. Superhorizon Perturbations and the Cosmic Microwave Background. https://doi.org/10.1103/physrevd.78.083012

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