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Related papers: The circles-in-the-sky signature for three spheric…

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We analyse the anisotropy of the cosmic microwave background (CMB) for the Poincare dodecahedron which is an example for a multi-connected spherical universe. We compare the temperature correlation function and the angular power spectrum…

Astrophysics · Physics 2009-11-10 R. Aurich , S. Lustig , F. Steiner

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…

An important, and potentially detectable, signature of a non-trivial topology for the universe is the presence of so called circles-in-the-sky in the cosmic microwave background (CMB). Recent searches, confined to antipodal and nearly…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-21 B. Mota , M. J. Reboucas , R. Tavakol

We study a multipole vector-based decomposition of cosmic microwave background (CMB) data in order to search for signatures of a multiconnected topology of the universe. Using 10^6 simulated maps, we analyse the multipole vector…

Astrophysics · Physics 2015-05-13 P. Bielewicz , A. Riazuelo

What is the shape of space is a long-standing question in cosmology. In this talk I review recent advances in cosmic topology since it has entered a new era of experimental tests. High redshift surveys of astronomical sources and accurate…

Astrophysics · Physics 2015-06-24 Jean-Pierre Luminet

The Cosmic Microwave Background (CMB) power spectrum derived from the first year WMAP data demonstrates an intriguing lack of power at large scales that cannot be accounted for within the framework of the standard cosmological model. We…

Astrophysics · Physics 2009-11-11 Anastasia Niarchou , Andrew H. Jaffe

A recent paper by Hsu & Zee (physics/0510102) suggests that if a Creator wanted to leave a message for us, and she wanted it to be decipherable to all sentient beings, then she would place it on the most cosmic of all billboards, the Cosmic…

Popular Physics · Physics 2007-05-23 Douglas Scott , J. P. Zibin

A non-trivial spatial topology of the Universe is a potentially observable attribute, which can be probed through the circles-in-the-sky for all locally homogeneous and isotropic universes with no assumptions on the cosmological parameters.…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-21 M. J. Reboucas

[Abridged] An observable signature of a detectable nontrivial spatial topology of the Universe is the circles-in-the-sky in the CMB sky. In the most general search, pairs of circles with deviation from antipodality $0^\circ \leq \theta \leq…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-10 G. I. Gomero , B. Mota , M. J. Reboucas

The immediate observational consequence of a non-trivial spatial topology of the Universe is that an observer could potentially detect multiple images of radiating sources. In particular, a non-trivial topology will generate pairs of…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-23 S. D. P. Vitenti , M. P. Lima , M. J. Reboucas

The existence of concentric low variance circles in the CMB sky, generated by black-hole encounters in an aeon preceding our big bang, is a prediction of the Conformal Cyclic Cosmology. Detection of three families of such circles in WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Amir Hajian

If the universe is finite and smaller than the distance to the surface of last scatter, then the signature of the topology of the universe is writ large on the microwave background sky. We show that the microwave background will be…

Astrophysics · Physics 2009-10-30 Neil Cornish , David Spergel , Glenn Starkman

It has been suggested by Roukema and coworkers (hereafter R04) that the topology of the Universe as probed by the ``matched circles'' method using the first year release of the WMAP CMB data, might be that of the Poincar\'e dodecahedral…

Astrophysics · Physics 2008-04-24 B. S. Lew , B. F. Roukema

In a Universe with a detectable nontrivial spatial topology the last scattering surface contains pairs of matching circles with the same distribution of temperature fluctuations --- the so-called circles-in-the-sky. Searches undertaken for…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-20 B. Mota , M. J. Reboucas , R. Tavakol

This article investigates the signature of the seventeen multi-connected flat spaces in cosmic microwave background (CMB) maps. For each such space it recalls a fundamental domain and a set of generating matrices, and then goes on to find…

The first-year WMAP data taken at their face value hint that the Universe might be slightly positively curved and therefore necessarily finite, since all spherical (Clifford-Klein) space forms M^3 = S^3/Gamma, given by the quotient of S^3…

Astrophysics · Physics 2009-11-11 R. Aurich , S. Lustig , F. Steiner

The cosmic microwave background radiation allows us to measure both the geometry and topology of the universe. It has been argued that the COBE-DMR data already rule out models that are multiply connected on scales smaller than the particle…

Astrophysics · Physics 2009-10-31 Neil J. Cornish , David N. Spergel

We investigate the question of the suppression of the CMB power spectrum for the lowest multipoles in closed Universes. The intrinsic reason for a lowest cutoff in closed Universes, connected with the discrete spectrum of the wavelength, is…

High Energy Physics - Theory · Physics 2009-11-11 Zhuo-Yi Huang , Bin Wang , Elcio Abdalla , Ru-Keng Su

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

If the universe is finite and smaller than the distance to the surface of last scatter, then the signature of the topology of the universe is writ on the microwave background sky. Previous efforts to search for this topology have focused on…

General Relativity and Quantum Cosmology · Physics 2016-02-09 Neil J. Cornish , David N. Spergel , Glenn D. Starkman
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