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arXiv · 1006.3321

On the Possibility of Anisotropic Curvature in Cosmology

Tomi S. Koivisto·David F. Mota·Miguel Quartin·Tom G. Zlosnik
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Abstract

In addition to shear and vorticity a homogeneous background may also exhibit anisotropic curvature. Here a class of spacetimes is shown to exist where the anisotropy is solely of the latter type, and the shear-free condition is supported by a canonical, massless 2-form field. Such spacetimes possess a preferred direction in the sky and at the same time a CMB which is isotropic at the background level. A distortion of the luminosity distances is derived and used to test the model against the CMB and supernovae (using the Union catalog), and it is concluded that the latter exhibit a higher-than-expected dependence on angular position. It is shown that future surveys could detect a possible preferred direction by observing ~ 20 / (Ω_{k0}^2) supernovae over the whole sky.

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Tomi S. Koivisto, David F. Mota, Miguel Quartin, Tom G. Zlosnik. 2010-11-22. On the Possibility of Anisotropic Curvature in Cosmology. https://doi.org/10.1103/physrevd.83.023509

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