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arXiv · gr-qc/0108073

Kaluza-Klein anisotropy in the CMB

John D Barrow·Roy Maartens
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Abstract

We show that 5-dimensional Kaluza-Klein graviton stresses can slow the decay of shear anisotropy on the brane to observable levels, and we use cosmic microwave background anisotropies to place limits on the initial anisotropy induced by these stresses. An initial shear to Hubble distortion of only \sim 10^{-3}Ω_0h_0^2 at the 5D Planck time would allow the observed large-angle CMB signal to be a relic mainly of KK tidal effects.

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John D Barrow, Roy Maartens. 2002-01-12. Kaluza-Klein anisotropy in the CMB. https://doi.org/10.1016/s0370-2693(02)01552-6

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