Is the cold spot responsible for the CMB North-South asymmetry?

Abstract

Several intriguing phenomena, unlikely within the standard inflationary cosmology, were reported in the cosmic microwave background (CMB) data from WMAP and appear to be uncorrelated. Two of these phenomena, termed CMB anomalies, are representative of their disparate nature: the North-South asymmetry in the CMB angular-correlation strength, inconsistent with an isotropic universe, and the cold spot, producing a significant deviation from Gaussianity. We find a cause-effect relationship between them, at medium angular scales (l = 11 - 20): we show that a successive diminution of the cold spot (absolute-value) temperature implies a monotonic decrease of the North-South asymmetry power, and moreover we find that the cold spot supplies 60% of such power.

5 pages, 2 Postscript figures

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