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Polarizing bubble collisions

Czech, Bartłomiej·Larjo, Klaus·Levi, Thomas S.·Sigurdson, Kris·Kleban, Matthew
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Abstract

We predict the polarization of cosmic microwave background (CMB) photons that results from a cosmic bubble collision. The polarization is purely E-mode, symmetric around the axis pointing towards the collision bubble, and has several salient features in its radial dependence that can help distinguish it from a more conventional explanation for unusually cold or hot features in the CMB sky. The anomalous ''cold spot'' detected by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite is a candidate for a feature produced by such a collision, and the Planck satellite and other proposed surveys will measure the polarization on it in the near future. The detection of such a collision would provide compelling evidence for the string theory landscape.

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79 ASTRONOMY AND ASTROPHYSICSANISOTROPYASTROPHYSICSCOSMOLOGYPHOTONSPOLARIZATIONRELICT RADIATIONSTRING MODELSSTRING THEORYSYMMETRY

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Czech, Bartłomiej, Larjo, Klaus, Levi, Thomas S., Sigurdson, Kris, Kleban, Matthew. 2010-12-01. Polarizing bubble collisions. https://doi.org/10.1088/1475-7516%2F2010%2F12%2F023

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