Evidence of Vorticity and Shear at Large Angular Scales in the WMAP Data: A Violation of Cosmological Isotropy?

@article{Jaffe2005EvidenceOV,
  title={Evidence of Vorticity and Shear at Large Angular Scales in the WMAP Data: A Violation of Cosmological Isotropy?},
  author={Tess R. Jaffe and Anthony J. Banday and Hans Kristian Eriksen and Krzysztof M. Gorski and F. K. Hansen},
  journal={The Astrophysical Journal Letters},
  year={2005},
  volume={629},
  pages={L1 - L4}
}
Motivated by the large-scale asymmetry observed in the cosmic microwave background sky, we consider a specific class of anisotropic cosmological models—Bianchi type VIIh—and compare them to the WMAP first-year data on large angular scales. Remarkably, we find evidence of a correlation that is ruled out as a chance alignment at the 3 σ level. The best-fit Bianchi model corresponds to x = 0.55, Ω0 = 0.5, a rotation axis in the direction (l, b) = (222°, -62°), shear 0 = 2.4 × 10-10, and a right… 
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References

SHOWING 1-10 OF 25 REFERENCES
Significance of the largest scale CMB fluctuations in WMAP
We investigate anomalies reported in the Cosmic Microwave Background maps from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite on very large angular scales and discuss possible
Cosmological parameters and the WMAP data revisited
Several recent papers have made claims about the detection of an asymmetric distribution of large-scale power in the cosmic microwave background (CMB) anisotropy as measured by the WMAP satellite. In
Asymmetries in the Cosmic Microwave Background Anisotropy Field
We report on the results from two independent but complementary statistical analyses of the Wilkinson Microwave Anisotropy Probe (WMAP) first-year data, based on the power spectrum and N-point
Testing the cosmological principle of isotropy: Local power spectrum estimates of the WMAP data
We apply the Gabor transform methodology proposed in (Hansen et al. 2002, 2003) to the WMAP data in order to test the statistical properties of the CMB fluctuation field and specifically to evaluate
A maximum likelihood analysis of the low cosmic microwave background multipoles from the Wilkinson Microwave Anisotropy Probe
The amplitudes of the quadrupole and octopole measured from the Wilkinson Microwave Anisotropy Probe (WMAP) appear to be lower than expected according to the concordance A cold dark matter (ACDM)
How Anisotropic is Our Universe?
TLDR
Large-scale cosmic microwave background anisotropies in homogeneous, globally anisotropic cosmologies are investigated and primordial anisotropy should have been fine tuned to be less than 10{sup {minus}3} of its natural value in the Planck era.
Detection of Non-Gaussianity in the Wilkinson Microwave Anisotropy Probe First-Year Data Using Spherical Wavelets
TLDR
The non-Gaussian detection in the Wilkinson Microwave Anisotropy Probe (WMAP) first-year data implies not only asymmetries north/south—like other previous WMAP analyses—but also a direct non- Gaussian detection.
Assessing the effects of foregrounds and sky removal in WMAP
Many recent analyses have indicated that large scale Wilkinson Microwave Anisotropy Probe (WMAP) data display anomalies that appear inconsistent with the standard cosmological paradigm. However, the
First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: The Angular Power Spectrum
We present the angular power spectrum derived from the first-year Wilkinson Microwave Anisotropy Probe (WMAP) sky maps. We study a variety of power spectrum estimation methods and data combinations
First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results
We present full-sky microwave maps in five frequency bands (23-94 GHz) from the Wilkinson Microwave Anisotropy Probe (WMAP) first-year sky survey. Calibration errors are less than 0.5%, and the low
...
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