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arXiv · 1404.3730

Tensor-induced B modes with no temperature fluctuations

Marc Kamionkowski·Liang Dai·Donghui Jeong
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Abstract

The recent indications for a tensor-to-scalar ratio $ r \simeq 0.2$ from BICEP2 measurements of the cosmic microwave background (CMB) B-mode polarization present some tension with upper limits $r \lesssim 0.1$ from measurements of CMB temperature fluctuations. Here we point out that tensor perturbations can induce B modes in the CMB polarization without inducing any temperature fluctuations nor E-mode polarization whatsoever, but only, at the expense of violating the Copernican principle. We present this mathematical possibility as a new ingredient for the model-builder's toolkit in case the tension between B modes and temperature fluctuations cannot be resolved with more conventional ideas.

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Marc Kamionkowski, Liang Dai, Donghui Jeong. 2014-06-02. Tensor-induced B modes with no temperature fluctuations. https://doi.org/10.1103/physrevd.89.107302

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