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arXiv · gr-qc/9305019

New Restrictions on Spatial Topology of the Universe from Microwave Background Temperature Fluctuations

A. A. Starobinsky
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Abstract

If the Universe has the topology of a 3-torus ($T^3$), then it follows from recent data on large-scale temperature fluctuations $ΔT/T$ of the cosmic microwave background that either the minimal size of the torus is at least of the order of the present cosmological horizon, or the large-scale $ΔT/T$ pattern should have a symmetry plane (in case of the effective $T^1$ topology) or a symmetry axis (in case of the effective $T^2$ topology), the latter possibility being probably excluded by the data.

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A. A. Starobinsky. 1993-05-23. New Restrictions on Spatial Topology of the Universe from Microwave Background Temperature Fluctuations. https://arxiv.org/abs/gr-qc/9305019

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