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Related papers: Constraints on Compact Hyperbolic Spaces from COBE

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The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. For compact topologies, the two main effects on the CMB are: (1) the…

Astrophysics · Physics 2011-04-15 J. Richard Bond , Dmitri Pogosyan , Tarun Souradeep

We calculate the CMB anisotropy in compact hyperbolic universe models using the regularized method of images described in paper-I, including the 'line-of-sight `integrated Sachs-Wolfe' effect, as well as the last-scattering surface terms.…

Astrophysics · Physics 2009-10-31 J. Richard Bond , Dmitry Pogosyan , Tarun Souradeep

CMB anisotropy measurements have brought the issue of global topology of the universe from the realm of theoretical possibility to within the grasp of observations. The global topology of the universe modifies the correlation properties of…

Astrophysics · Physics 2009-10-31 J. Richard Bond , Dmitry Pogosyan , Tarun Souradeep

The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. We have developed a new method for calculating the CMB anisotropy in…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Dmitry Pogosyan , J. Richard Bond

The cosmic microwave background (CMB) is a unique probe of cosmological parameters and conditions. There is a connection between anisotropy in the CMB and the topology of the Universe. Adopting a universe with the topology of a 3-Torus, or…

Astrophysics · Physics 2009-10-22 Angelica de Oliveira-Costa , George F. Smoot

In this paper, the cosmic microwave background (CMB) anisotropy in a multiply-connected compact flat 3-torus model with the cosmological constant is investigated. Using the COBE-DMR 4-year data, a full Bayesian analysis revealed that the…

Astrophysics · Physics 2009-10-31 Kaiki Taro Inoue

We revisit the observational constraints on compact(closed) hyperbolic(CH) models from cosmic microwave background(CMB). We carry out Bayesian analyses for CH models with volume comparable to the cube of the present curvature radius using…

Astrophysics · Physics 2009-11-06 Kaiki Taro Inoue

The effect of a non-trivial topology on the temperature correlations on the cosmic microwave background (CMB) in a small compact hyperbolic universe with volume comparable to the cube of the curvature radius is investigated. Because the…

Astrophysics · Physics 2014-10-13 Kaiki Taro Inoue , Kenji Tomita , Naoshi Sugiyama

In recent years, the large angle COBE--DMR data have been used to place constraints on the size and shape of certain topologically compact models of the universe. Here we show that this approach does not work for generic compact models. In…

Astrophysics · Physics 2008-11-26 Neil Cornish , David Spergel , Glenn Starkman

When considering the statistical properties of a bundle of cosmic microwave background (CMB) photons propagating through space, the effect of `mixing geodesics' appears with a distinct signature that depends on the geometry of space. In a…

Astrophysics · Physics 2011-05-10 V. G. Gurzadyan , S. Torres

Measurements of CMB anisotropy are ideal experiments for discovering the non-trivial global topology of the universe. To evaluate the CMB anisotropy in multiply-connected compact cosmological models, one needs to compute eigenmodes of the…

Astrophysics · Physics 2007-05-23 Kaiki Taro Inoue

We study the effect of global topology of the spatial geometry on the cosmic microwave background (CMB) for closed flat and closed hyperbolic models in which the spatial hypersurface is multiply connected. If the CMB temperature…

Astrophysics · Physics 2013-09-06 Kaiki Taro Inoue

The significance to which the cosmic microwave background observations by the satellite COBE can be used to refute a specific observationally based hypothesis for the global topology (3-manifold) of the Universe is investigated, by a new…

Astrophysics · Physics 2009-10-31 Boudewijn F. Roukema

The properties of the Cosmic Microwave Background (CMB) radiation must be different in flat, positively and negatively curved universes. This fact leads to a direct way of determining the geometry of the universe. The signature of the…

Astrophysics · Physics 2018-03-28 V. G. Gurzadyan

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

Astrophysics · Physics 2007-05-23 Amir Hajian , Tarun Souradeep

We impose constraints on the topology of the Universe determined from a search for matched circles in the cosmic microwave background (CMB) temperature anisotropy patterns of the 7-year WMAP data. We pay special attention to the sensitivity…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-19 P. Bielewicz , A. J. Banday , K. M. Gorski

The temperature and polarization of the cosmic microwave background (CMB), as measured today, may offer key insights into the topology of the early universe prior to inflation, for example, by discriminating between flat and warped…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-29 Miguel-Angel Sanchis-Lozano

The recent study of BOOMERanG 150 GHz Cosmic Microwave Background (CMB) radiation maps have detected ellipticity of the temperature anisotropy spots independent on the temperature threshold. The effect has been found for spots up to several…

We study the possibility for constraining the topology of the Universe by means of the matched circles statistic applied to polarised cosmic microwave background (CMB) anisotropy maps. The advantages of using the CMB polarisation maps in…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-09 P. Bielewicz , A. J. Banday , K. M. Gorski

The geodesics followed by cosmic microwave background (CMB) photons show different behaviours depending on the geometry of space. Namely, the effect of `mixing geodesics' predicts a distinct signature in CMB maps: threshold-independent…

Astrophysics · Physics 2007-05-23 V. G. Gurzadyan , S. Torres
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