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Title: The topology and size of the universe from CMB temperature and polarization data

We analyze seven year and nine year WMAP temperature maps for signatures of three finite flat topologies M{sub 0} = T{sup 3}, M{sub 1} = T{sup 2} × R{sup 1}, and M{sub 2} = S{sup 1} × R{sup 2}. We use Monte-Carlo simulations with the Feldman-Cousins method to obtain confidence intervals for the size of the topologies considered. We analyze the V, W, and Q frequency bands along with the ILC map and find no significant difference in the results. The 95.5% confidence level lower bound on the size of the topology is 1.5L{sub 0} for M{sub 0}, 1.4L{sub 0} for M{sub 1}, and 1.1L{sub 0} for M{sub 2}, where L{sub 0} is the radius of the last scattering surface. Our results agree very well with the recently released results from the Planck temperature data. We show that the likelihood function is not Gaussian in the size, and therefore simulations are important for obtaining accurate bounds on the size. We then introduce the formalism for including polarization data in the analysis. The improvement that we find from WMAP polarization maps is small because of the high level of instrumental noise, but our forecast for Planck maps shows a much bettermore » improvement on the lower bound for L. For the M{sub 0} topology we expect an improvement on the lower bound of L from 1.7L{sub 0} to 1.9L{sub 0} at 95.5% confidence level. Using both polarization and temperature data is important because it tests the hypothesis that deviations in the TT spectrum at small l originate in the primordial perturbation spectrum.« less
Authors:
 [1] ; ;  [2]
  1. Department of Physics, University of Auckland, Private Bag 92019, Auckland (New Zealand)
  2. Department of Physics, University of California at San Diego, La Jolla, CA 92093 (United States)
Publication Date:
OSTI Identifier:
22282701
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; COMPUTERIZED SIMULATION; COSMOLOGY; MONTE CARLO METHOD; NOISE; PERTURBATION THEORY; POLARIZATION; SCATTERING; TOPOLOGY; UNIVERSE