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Constraints On The Topology Of The Universe From The WMAP First-Year Sky Maps

N. G. Phillips·A. Kogut
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Abstract

We compute the covariance expected between the spherical harmonic coefficients $a_{\ell m}$ of the cosmic microwave temperature anisotropy if the universe had a compact topology. For fundamental cell size smaller than the distance to the decoupling surface, off-diagonal components carry more information than the diagonal components (the power spectrum). We use a maximum likelihood analysis to compare the Wilkinson Microwave Anisotropy Probe first-year data to models with a cubic topology. The data are compatible with finite flat topologies with fundamental domain $L > 1.2$ times the distance to the decoupling surface at 95% confidence. The WMAP data show reduced power at the quadrupole and octopole, but do not show the correlations expected for a compact topology and are indistinguishable from infinite models.

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N. G. Phillips, A. Kogut. 2004-04-20. Constraints On The Topology Of The Universe From The WMAP First-Year Sky Maps. https://doi.org/10.1086/432861

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