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How Anisotropic is our Universe?

Emory. F. Bunn·Pedro Ferreira·Joseph Silk
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Abstract

Large-scale cosmic microwave background anisotropies in homogeneous, globally anisotropic cosmologies are investigated. We perform a statistical analysis in which the four-year data from the Cosmic Background Explorer satellite is searched for the specific anisotropy patterns predicted by these models and thereby set definitive upper limits on the amount of shear, $(σ/H)_0$ and vorticity, $(ω/H)_0$, which are orders of magnitude stronger than previous constraints. We comment on how these results might impact our understanding of primordial global anisotropy.

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Emory. F. Bunn, Pedro Ferreira, Joseph Silk. 1996-05-20. How Anisotropic is our Universe?. https://doi.org/10.1103/physrevlett.77.2883

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