Constraints on the Topology of the Universe from the Wilkinson Microwave Anisotropy Probe First-Year Sky Maps
Abstract
We compute the covariance expected between the spherical harmonic coefficients alm of the cosmic microwave temperature anisotropy if the universe had a compact topology. For a fundamental cell size smaller than the distance to the decoupling surface, off-diagonal components carry more information than the diagonal components (the power spectrum). We use a maximum likelihood analysis to compare the Wilkinson Microwave Anisotropy Probe (WMAP) first-year data to models with a cubic topology. The data are compatible with finite flat topologies with fundamental domain L>1.2 times the distance to the decoupling surface at a 95% confidence level. The WMAP data show reduced power at the quadrupole and octopole, but they do not show the correlations expected for a compact topology and are indistinguishable from infinite models.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2006
- DOI:
- 10.1086/432861
- arXiv:
- arXiv:astro-ph/0404400
- Bibcode:
- 2006ApJ...645..820P
- Keywords:
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- Cosmology: Cosmic Microwave Background;
- Cosmology: Observations;
- Astrophysics
- E-Print:
- 16 pages, 5 figures