On the Large Scale CMB Polarization

Abstract

We discuss the large scale polarization of the cosmic microwave background induced by the anisotropy of the spatial geometry of our universe. Assuming an eccentricity at decoupling of about $0.6410^{-2}$, we find an average large scale polarization $\hat{I}”T_{pol}/T_0=(0.5-1.0)10^{-6}$. We suggest that the fortcoming polarization data at large scales from Planck will be able to discriminate between our proposal and the generally accepted reionization scenario.

9 pages, revised version accepted for publication on Mont. Not. Roy. Astr. Soc.