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Related papers: Multipole analysis in cosmic topology

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The large-angular-scale falloff in the autocorrelation function for the cosmic microwave background (CMB) temperature has long intrigued cosmologists and fueled speculation about suppressed superhorizon power. Here we highlight an…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-13 Jahmour J. Givans , Marc Kamionkowski

We present a blind multi-detector multi-component spectral matching method for all sky observations of the cosmic microwave background, working on the spherical harmonics basis. The method allows to estimate on a set of observation maps the…

Astrophysics · Physics 2007-05-23 G. Patanchon , H. Snoussi , J. F. Cardoso , J. Delabrouille

The recent measurements of the power spectrum of Cosmic Microwave Background anisotropies are consistent with the simplest inflationary scenario and big bang nucleosynthesis constraints. However, these results rely on the assumption of a…

The observed CMBR dipole is generally interpreted as the consequence of the peculiar motion of the Sun with respect to the reference frame of the CMBR. This article proposes an alternative interpretation in which the observed dipole is the…

General Relativity and Quantum Cosmology · Physics 2009-12-30 David Langlois

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

Cosmic microwave background (CMB) anisotropy may result from both scalar and tensor perturbations. For a sufficiently narrow range of angular scales, CMB perturbations can be characterized by four parameters. Results from the Cosmic…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Lloyd Knox , Edward W. Kolb

We present a new method for multi-component power spectra estimation in multi-frequency observations of the CMB. Our method is based on matching a model to the cross and auto power spectra of observed maps. All the component power spectra…

Astrophysics · Physics 2015-06-24 Guillaume Patanchon

The problem of separation of different signals in the Cosmic Microwave Background (CMB) radiation using the difference in their statistics is analyzed. Considering samples of sequences which model the CMB as a superposition of signals, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 S. Mirzoyan , E. Poghosian

Part of the CMB polarization signal in the direction of galaxy clusters is produced by Thomson scattering of the CMB temperature quadrupole. In principle this allows measurement of the CMB power spectrum harmonic $C_2(z)$ with higher…

Astrophysics · Physics 2009-09-29 Jamie Portsmouth

We investigate the hemispherical power asymmetry in the cosmic microwave background on small angular scales. We find an anomalously high asymmetry in the multipole range l=601-2048, with a naive statistical significance of 6.5 sigma.…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-30 Samuel Flender , Shaun Hotchkiss

Anomalies of the cosmic microwave background (CMB) maps have been widely acquainted nowadays from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite to the Planck satellite. One of the anomalies is a multipole alignment from $l=2$ to…

High Energy Astrophysical Phenomena · Physics 2014-06-30 Lixiong Gan , Yuan-Chuan Zou , Zi-Gao Dai

This article describes the Cosmic Microwave Background anisotropies expected in a closed universe with the topology of a lens space L(p,q) and with density parameter Omega_0 close to 1. It provides the first simulated maps for such spaces…

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

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological…

Astrophysics · Physics 2009-09-29 Christopher O'Dell

Observation of the fine structures (anisotropies, polarization, spectral distortions) of the Cosmic Microwave Background (CMB) is hampered by instabilities, 1/f noise and asymmetries of the radiometers used to carry on the measurements.…

This paper covers several techniques of intercomparison of Cosmic Microwave Background (CMB) anisotropy experiments and models of structure formation. It presents the constraints on several cosmological parameters using current CMB…

Astrophysics · Physics 2007-05-23 Graca Rocha

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 standard model of cosmology, {\Lambda}CDM, is the simplest model that matches the current observations, but it relies on two hypothetical components, to wit, dark matter and dark energy. Future galaxy surveys and cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-13 Cyrille Doux , Mariana Penna-Lima , Sandro D. P. Vitenti , Julien Tréguer , Eric Aubourg , Ken Ganga

A simple algorithm which gives the multipole vectors in terms of the roots of a polynomial is given. We find that the reported alignmet of the low l multipole vectors can be summarised as an anti-alignmet of these with the dipole direction.…

Astrophysics · Physics 2008-12-18 Robert C. Helling , Peter Schupp , Tiberiu Tesileanu

The Cosmological Principle assumes a statistically isotropic Universe, but the Cosmic Microwave Background (CMB) exhibits some anomalous statistical features, such as the hemispherical power asymmetry, that challenge this core assumption.…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Javier Carrón Duque , Mikel Martin Barandiaran , Joseba Martínez-Arrizabalaga

I propose a mechanism that would explain the near alignment of the low order multipoles of the cosmic microwave background (CMB). This mechanism supposes a large-scale cosmic magnetic field that tends to align the cyclotron orbit axes of…

Astrophysics · Physics 2007-05-23 Michael J. Longo
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