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This article describes the computation of cosmic microwave background anisotropies in a universe with multi-connected spatial sections and focuses on the implementation of the topology in standard CMB computer codes. The key ingredient is…

Astrophysics · Physics 2009-11-07 Alain Riazuelo , Jean-Philippe Uzan , Roland Lehoucq , Jeffrey Weeks

Scattering of cosmic microwave background (CMB) radiation in galaxy clusters induces a polarization signal proportional to the CMB quadrupole anisotropy at the cluster's location and look-back time. A survey of such remote quadrupole…

Astrophysics · Physics 2007-05-23 Emory F. Bunn

Since this is a meeting on inflation the title of this talk should probably have been ``The cosmos as a lab for inflation''. I will illustrate how, by combining WMAP observations of the cosmic microwave background (CMB) with smaller scales…

Astrophysics · Physics 2007-05-23 Licia verde

WMAP and Planck may have uncovered several anomalies in the full CMB sky that could indicate possible new physics driving the growth of density fluctuations in the early Universe. These include an unusually low power at the largest scales…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Fulvio Melia

We investigate large-angle scale temperature anisotropy in the Cosmic Microwave Background (CMB) with the Wilkinson Microwave Anisotropy Probe (WMAP) data and model the large-angle anomalies as the effect of the CMB quadrupole anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Li-Ping He , Quan Guo

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce…

Astrophysics · Physics 2009-11-10 Simon Prunet , Jean-Philippe Uzan , Francis Bernardeau , Tristan Brunier

Previous claims of significant evidence for mirror-parity in the large-scale cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP) experiment have been recently echoed in the first study of isotropy and…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-20 Assaf Ben-David , Ely D. Kovetz

Large-scale modes in the temperature anisotropy power spectrum C_l measured by the Wilkinson Microwave Anisotropy Probe (WMAP), seem to have lower amplitudes (C_2, C_3 and C_4) than that expected in the so called concordance LCDM model. In…

Astrophysics · Physics 2009-11-07 E. Gaztanaga , J. Wagg , T. Multamaki , A. Montana , D. H. Hughes

In this talk, I review some recent work on cosmic microwave background (CMB) anisotropies in an open universe. I emphasize that the observed CMB anisotropies are still consistent with a low value of $\Omega$, and I address the question of…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski

We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

We calculate the large scale polarization of the cosmic microwave background induced by the anisotropy of the spatial geometry of our universe. Assuming an eccentricity at decoupling of about $0.64 10^{-2}$, we find $\Delta T_{pol}/ T_0…

Astrophysics · Physics 2007-10-24 Paolo Cea

The anisotropies of the cosmic microwave background (CMB) are computed for the half-turn space E_2 which represents a compact flat model of the Universe, i.e. one with finite volume. This model is inhomogeneous in the sense that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 R. Aurich , S. Lustig

The apparent alignment of the cosmic microwave background multipoles on large scales challenges the standard cosmological model. Scalar field inflation is isotropic and cannot account for the observed alignment. We explore the imprints, a…

Astrophysics · Physics 2010-04-14 Christian G. Boehmer , David F. Mota

In a recent paper, Gurzadyan & Penrose claim to have found directions in the sky around which there are multiple concentric sets of annuli with anomalously low variance in the cosmic microwave background (CMB). These features are presented…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-23 Adam DeAbreu , Dagoberto Contreras , Douglas Scott

Several anomalies appear to be present in the large-angle cosmic microwave background (CMB) anisotropy maps of WMAP. One of these is a lack of large-scale power. Because the data otherwise match standard models extremely well, it is natural…

Astrophysics · Physics 2008-12-18 Emory F. Bunn , Austin Bourdon

The standard cosmological model, which assumes statistical isotropy and parity invariance, predicts the absence of correlations between even-parity and odd-parity observables of the cosmic microwave background (CMB). Contrary to these…

The low multipole anomalies of the Cosmic Microwave Background has received much attention during the last few years. It is still not ascertained whether these anomalies are indeed primordial or the result of systematics or foregrounds. An…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-01 M. Hansen , J. Kim , A. M. Frejsel , S. Ramazanov , P. Naselsky , W. Zhao , C. Burigana

We have investigated the cosmic microwave background (CMB) anisotropy in closed multiply connected universes (flat and hyperbolic) with low matter density. We show that the COBE constraints on these low matter density models with…

Astrophysics · Physics 2016-08-30 Kaiki Taro Inoue

A fundamental assumption in cosmology is that of statistical isotropy - that the universe, on average, looks the same in every direction in the sky. Statistical isotropy has recently been tested stringently using Cosmic Microwave Background…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-14 Caroline Zunckel , Dragan Huterer , Glenn D. Starkman

The plane-mirror symmetry previously noticed in the Cosmic Microwave Background (CMB) temperature anisotropy maps of Wilkinson Microwave Anisotropy Probe is shown to possess certain anomalous properties. The degree of the randomness…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 V. G. Gurzadyan , T. Ghahramanyan , A. L. Kashin , H. G. Khachatryan , A. A. Kocharyan , H. Kuloghlian , D. Vetrugno , G. Yegorian
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