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Related papers: Kolmogorov cosmic microwave background sky

200 papers

The Cosmic Microwave Background (CMB) provides a precious window on fundamental physics at very high energy scales, possibly including quantum gravity, GUTs and supersymmetry. The CMB has already enabled defect-based rivals to inflation to…

Astrophysics · Physics 2009-09-11 John Ellis

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…

y-type spectral distortions of the cosmic microwave background allow us to detect clusters and groups of galaxies, filaments of hot gas and the non-uniformities in the warm hot intergalactic medium. Several CMB experiments (on small areas…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-13 Rashid A. Sunyaev , Rishi Khatri

In a recent paper, Gurzadyan & Penrose claim to have found directions on the sky centred on which are circles of anomalously low variance in the cosmic microwave background (CMB). These features are presented as evidence for a particular…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Adam Moss , Douglas Scott , James P. Zibin

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

The fluctuations in the temperature and polarization of the cosmic microwave background are described by a hierarchy of Boltzmann equations. In its integral form, this Boltzmann hierarchy can be converted from the usual Fourier-space base…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-02 Paulo H. F. Reimberg , L. Raul Abramo

We have studied the cosmic microwave background (CMB) map looking for features beyond cosmological isotropy. We began by tiling the CMB variance map (which are produced by different smoothing scales) with stripes of different sizes along…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-12 MohammadHossein Jamshidi , Abdolali Banihashemi , Nima Khosravi

We introduce a new family of primordial cosmological perturbations that are not described by traditional power spectra. At the linear level, these perturbations live in the kernel of the spatial Laplacian operator, and thus we call them…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 Niayesh Afshordi , Matthew C. Johnson

In our recent paper (Yadav et al. 2007) we described a fast cubic (bispectrum) estimator of the amplitude of primordial non-Gaussianity of local type, f_{NL}, from a combined analysis of the Cosmic Microwave Background (CMB) temperature and…

Non-Gaussian imprints on the cosmic microwave background radiation (CBR) sky are within the grasp of current experiments. A clear non-Gaussian signature would be point-like sources. We have examined the nature of possible point sources that…

Astrophysics · Physics 2009-09-25 Xiaochun Luo , J. Silk

We performed a visual and numeric analysis of the deviation of the microwave background temperature on WMAP maps. We proved that the microwave background inhomogeneities possess the property of the central symmetry resulting from the two…

General Physics · Physics 2013-01-15 Iurii Kudriavtcev , Dmitry A. Semenov

We evaluate the expected level of foreground contamination to the cosmic microwave background (CMB) polarised radiation, focusing on the diffuse emission from our own Galaxy. In particular, we perform a first attempt to simulate an all sky…

Astrophysics · Physics 2015-06-24 Carlo Baccigalupi

One of the most striking features found in the cosmic microwave background data is the presence of an anomalous Cold Spot (CS) in the temperature maps made by the Wilkinson Microwave Anisotropy Probe (WMAP). This CS has been interpreted as…

Astrophysics · Physics 2009-06-23 J. A. R. Cembranos , A. de la Cruz-Dombriz , A. Dobado , A. L. Maroto

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

In this research, we present an alternative methodology to search for ring-like structures in the sky with unusually large temperature gradients, namely Hawking points (HP), in the Cosmic Microwave Background (CMB), which are possible…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-09 Melissa Lopez , Pietro Bonizzi , Kurt Driessens , Gideon Koekoek , Jacco de Vries , Ronald Westra

Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-13 Stephen M. Feeney , Matthew C. Johnson , Daniel J. Mortlock , Hiranya V. Peiris

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…

We estimate the level of confusion to Cosmic Microwave Background anisotropy measurements caused by extragalactic infrared sources. CMB anisotropy observations at high resolution and high frequencies are especially sensitive to this…

Astrophysics · Physics 2009-10-28 Eric Gawiser , George F. Smoot

Non-Gaussian distributions of cosmic microwave background (CMB) anisotropies have been proposed to reconcile the discrepancies between different experiments at half-degree scales (Coulson et al. 1994). Each experiment probes a different…

Astrophysics · Physics 2009-10-22 Xiaochun Luo

Measurements of the cosmic microwave background (CMB) radiation provide a unique opportunity for a direct study of the primordial cosmic plasma at redshift z ~1000. The angular power spectra of temperature and polarisation fluctuations are…

Astrophysics · Physics 2009-11-10 Marco Bersanelli , Davide Maino , Aniello Mennella