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arXiv · 1203.6029

Weak lensing B-modes on all scales as a probe of local isotropy

Cyril Pitrou·Jean-Philippe Uzan·Thiago S. Pereira
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Abstract

This article derives a multipolar hierarchy for the propagation of the weak-lensing shear and convergence in a general spacetime. The origin of B-modes, in particular on large angular scales, is related to the local isotropy of space. Known results assuming a Friedmann-Lemaître background are naturally recovered. The example of a Bianchi I spacetime illustrates our formalism and its implications for future observations are stressed.

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Cyril Pitrou, Jean-Philippe Uzan, Thiago S. Pereira. 2013-02-08. Weak lensing B-modes on all scales as a probe of local isotropy. https://doi.org/10.1103/physrevd.87.043003

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