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Probing Cosmic topology using CMB anisotropy

Tarun Souradeep·Dmitry Pogosyan·J. Richard Bond
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Abstract

The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. We have developed a new method for calculating the CMB anisotropy in models with nontrivial topology and apply it to open universe models with compact spatial topology. We conduct a Bayesian probability analysis for a selection of models which confronts the theoretical pixel-pixel temperature correlation function with the COBE-DMR data. Our results demonstrate that strong constraints on compactness arise: if the universe is small compared to the `horizon' size, correlations appear in the maps that are irreconcilable with the observations.

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Tarun Souradeep, Dmitry Pogosyan, J. Richard Bond. 1998-04-04. Probing Cosmic topology using CMB anisotropy. https://arxiv.org/abs/astro-ph/9804042

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