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arXiv · 1104.0015

The Topology and Size of the Universe from the Cosmic Microwave Background

Grigor Aslanyan·Aneesh V. Manohar
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Abstract

We study the possibility that the universe has compact topologies T^3, T^2 x R^1, or S^1 x R^2 using the seven-year WMAP data. The maximum likelihood 95% confidence intervals for the size L of the compact direction are 1.7 < L/L_0 < 2.1, 1.8 < L/L_0 < 2.0, 1.2 < L/L_0 < 2.1 for the three cases, respectively, where L_0=14.4 Gpc is the distance to the last scattering surface. An infinite universe is compatible with the data at 4.3 sigma. We find using a Bayesian analysis that the most probable universe has topology T^2 x R^1, with L/L_0=1.9.

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Grigor Aslanyan, Aneesh V. Manohar. 2011-06-30. The Topology and Size of the Universe from the Cosmic Microwave Background. https://doi.org/10.1088/1475-7516%2F2012%2F06%2F003

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