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Cosmic microwave background multipole alignments in slab topologies

James G. Cresswell·Andrew R. Liddle·Pia Mukherjee·Alain Riazuelo
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Abstract

Several analyses of the microwave sky maps from the Wilkinson Microwave Anisotropy Probe (WMAP) have drawn attention to alignments amongst the low-order multipoles. Amongst the various possible explanations, an effect of cosmic topology has been invoked by several authors. We focus on an alignment of the first four multipoles (\ell = 2 to 5) found by Land and Magueijo (2005), and investigate the distribution of their alignment statistic for a set of simulated cosmic microwave background maps for cosmologies with slab-like topology. We find that this topology does offer a modest increase in the probability of the observed value, but that even for the smallest topology considered the probability of the observed value remains below one percent.

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James G. Cresswell, Andrew R. Liddle, Pia Mukherjee, Alain Riazuelo. 2006-01-19. Cosmic microwave background multipole alignments in slab topologies. https://doi.org/10.1103/physrevd.73.041302

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