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arXiv · 1010.4304

The Odd-Parity CMB Bispectrum

Marc Kamionkowski·Tarun Souradeep
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Abstract

Measurement of the cosmic microwave background (CMB) bispectrum, or three-point correlation function, has now become one of the principle efforts in early-Universe cosmology. Here we show that there is a odd-parity component of the CMB bispectrum that has been hitherto unexplored. We argue that odd-parity temperature-polarization bispectra can arise, in principle, through weak lensing of the CMB by chiral gravitational waves or through cosmological birefringence, although the signals will be small even in the best-case scenarios. Measurement of these bispectra requires only modest modifications to the usual data-analysis algorithms. They may be useful as a consistency test in searches for the usual bispectrum and to search for surprises in the data.

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Marc Kamionkowski, Tarun Souradeep. 2010-10-20. The Odd-Parity CMB Bispectrum. https://doi.org/10.1103/physrevd.83.027301

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