English
Related papers

Related papers: Constraining topology in harmonic space

200 papers

Multiply connected space sections of the universe on a scale smaller than the horizon size can leave an imprint on cosmic microwave background polarization maps, in such a way that the so-called ``circles-in-the-sky'' method can be used to…

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

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

Spatial correlations of the cubic 3-torus topology are analysed using the Planck 2013 data. The spatial-correlation method for detecting multiply connected spaces is based on the fact that positions on the cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 R. Aurich

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

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

Given the wealth of increasingly accurate cosmological observations, especially the recent results from the WMAP, and the development of methods and strategies in the search for cosmic topology, it is reasonable to expect that we should be…

Astrophysics · Physics 2008-11-26 M. J. Reboucas , J. S. Alcaniz

The standard cosmological model does not determine the spatial topology of the universe. This article revisits the signature of a non-trivial topology on the properties of the cosmic microwave background anisotropies. We show that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Ophélia Fabre , Simon Prunet , Jean-Philippe Uzan

In the last decade, the study of the overall shape of the universe, called Cosmic Topology, has become testable by astronomical observations, especially the data from the Cosmic Microwave Background (hereafter CMB) obtained by WMAP and…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-19 Jean-Pierre Luminet

In this paper we pursue a new technique to search for evidence of a finite Universe, making use of a spherical mexican-hat wavelet decomposition of the microwave background fluctuations. Using the information provided by the wavelet…

Astrophysics · Physics 2009-11-07 G. Rocha , L. Cayon , R. Bowen , A. Canavezes , J. Silk , A. J. Banday , K. M. Gorski

Multi-connected universe models with space identification scales smaller than the size of the observable universe produce topological images of cosmic sources. We generalise to locally hyperbolic spaces the crystallographic method, aimed to…

Astrophysics · Physics 2011-05-23 Jean-Philippe Uzan , Roland Lehoucq , Jean-Pierre Luminet

We analyze seven year and nine year WMAP temperature maps for signatures of three finite flat topologies M_0=T^3, M_1=T^2 x R^1, and M_2=S^1 x R^2. We use Monte-Carlo simulations with the Feldman-Cousins method to obtain confidence…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-12 Grigor Aslanyan , Aneesh V. Manohar , Amit P. S. Yadav

We impose constraints on the topology of the Universe determined from a search for matched circles in the temperature anisotropy patterns of the 7-year WMAP data. We pay special attention to the sensitivity of the method to residual…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 P. Bielewicz , A. J. Banday

Multi-connected Universe models with space idenfication scales smaller than the size of the observable universe produce topological images in the catalogs of cosmic sources. In this review, we present the recent developments for the search…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Jean-Philippe Uzan , Roland Lehoucq , Jean-Pierre Luminet

A test space is the set of outcome-sets associated with a collection of experiments. This notion provides a simple mathematical framework for the study of probabilistic theories -- notably, quantum mechanics -- in which one is faced with…

Quantum Physics · Physics 2009-11-10 Alexander Wilce

We investigate to what extent the cosmic crystallographic methods aimed to detect the topology of the universe using catalogues of cosmic objects would be damaged by various observational uncertainties. We find that the topological…

Astrophysics · Physics 2011-05-23 Roland Lehoucq , Jean-Philippe Uzan , Jean-Pierre Luminet

Non-trivial spatial topology of the Universe may give rise to potentially measurable signatures in the cosmic microwave background. We explore different machine learning approaches to classify harmonic-space realizations of the microwave…

In this work we investigate the standard deviation of the Cosmic Microwave Background (CMB) temperature gradient field as a signature for a multiply connected nature of the Universe. CMB simulations of a spatially infinite universe model…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-02 Ralf Aurich , Thomas Buchert , Martin J. France , Frank Steiner

We present a new technique for constraining the topology of the universe. The method exploits the existence of correlations in the phases of the spherical harmonic coefficients of the CMB temperature pattern associated with matched pairs of…

Astrophysics · Physics 2009-11-10 Patrick Dineen , Graca Rocha , Peter Coles

The two fundamental assumptions in cosmology are that the Universe is statistically homogeneous and isotropic when averaged on large scales. Given the big implication of these assumptions, there has been a lot of statistical tests carried…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Yabebal Fantaye
‹ Prev 1 2 3 10 Next ›