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Constraining topology with the CMB

Angelica de Oliveira-Costa·George F. Smoot·Alexei A. Starobinsky
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Abstract

We present a new data analysis method to study rectangular T^3 ``small universes" with one or two of its dimensions significantly smaller than the present horizon (which we refer to as T^1- and T^2-models, respectively). We find that the 4 year COBE/DMR data set a lower limit on the smallest cell size for T^1- and T^2-models of 3000h^{-1} Mpc, at 95% confidence, for a scale invariant power spectrum (n=1).

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Angelica de Oliveira-Costa, George F. Smoot, Alexei A. Starobinsky. 1997-05-16. Constraining topology with the CMB. https://arxiv.org/abs/astro-ph/9705125

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