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The circles-in-the-sky signature for three spherical universes

R. Aurich·S. Lustig·F. Steiner
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Abstract

The mysteriously low CMB power on the largest scales might point to a Universe which consists of a multi-connected space. In addition to a suppression of large-scale power, a multi-connected space can be revealed by its circles-in-the-sky signature. In this paper, a detailed search for this signature is carried out for those three homogeneous multi-connected spherical space forms that lead to the smallest large-scale power. A simultaneous search for all occurring paired circles is made using filtered CMB sky maps which enhance the ordinary Sachs-Wolfe contribution. A marginal hint is found for the right-handed Poincare dodecahedron at Omega_tot = 1.015 and for the right-handed binary tetrahedral space at Omega_tot = 1.068. However, due to the complicated noise and foreground structure of the available microwave sky maps, we cannot draw firm conclusions from our findings.

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R. Aurich, S. Lustig, F. Steiner. 2005-10-31. The circles-in-the-sky signature for three spherical universes. https://doi.org/10.1111/j.1365-2966.2006.10296.x

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