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We examine all-sky cosmic microwave background (CMB) temperature maps on large angular scales to compare their consistency with two scenarios: the standard inflationary quantum picture, and a distribution constrained to have a universal…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-13 Nathaniel Selub , Frederick Wehlen , Craig Hogan , Stephan S. Meyer

We discuss how an extended foreground of the cosmic microwave background (CMB) can account for the anomalies in the low multipoles of the CMB anisotropies. The distortion needed to account for the anomalies is consistent with a cold spot…

Astrophysics · Physics 2009-11-11 L. Raul Abramo , Laerte Sodre , Carlos Alexandre Wuensche

One of the most intriguing hints of a departure from the standard cosmological model is a large-scale dipolar power asymmetry in the cosmic microwave background (CMB). If not a statistical fluke, its origins must lie in the modulation of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-23 J. P. Zibin , D. Contreras

One of the major predictions of inflation is the existence of a stochastic background of cosmological gravitational waves (GW). These gravitational waves can induce significant temperature anisotropies in the Cosmic Microwave Background…

Astrophysics · Physics 2009-11-07 Alessandro Melchiorri , Carolina Odman

We investigate the ability to constrain oscillatory features in the primordial power spectrum using current and future cosmic microwave background observations. In particular, we study the observability of an oscillation arising from…

Astrophysics · Physics 2011-05-12 Takemi Okamoto , Eugene A. Lim

The cosmic microwave background radiation is supposed to be Gaussian and this hypothesis is in good agreement with the recent very accurate measurements. Nonetheless a tiny amount of non-Gaussianity is predicted by the standard inflation…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-06 Davide Pietrobon

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce…

Astrophysics · Physics 2009-11-10 Simon Prunet , Jean-Philippe Uzan , Francis Bernardeau , Tristan Brunier

We present simulations of the Cosmic Microwave Background Radiation (CMBR) power spectrum for a class of mixed, non-Gaussian, primordial random fields. We assume a skew positive mixed model with adiabatic inflation perturbations plus…

Astrophysics · Physics 2009-11-10 Ana Paula Andrade , Carlos Alexandre Wuensche , Andre Luiz B. Ribeiro

We present posterior sample-based cosmic microwave background (CMB) constraints from Planck LFI and WMAP observations derived through global end-to-end Bayesian processing. We use these samples to study correlations between CMB, foreground,…

We study the inflation process of universe based on the renormalizable quantum gravity formulated as a conformal field theory (CFT). We show that the power-law CFT spectrum approaches to that of the Harrison-Zel'dovich-Peebles type as the…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-18 Ken-ji Hamada , Shinichi Horata , Tetsuyuki Yukawa

The cosmic microwave background (CMB) temperature distribution measured by the Wilkinson Microwave Anisotropy Probe (WMAP) exhibits anomalously low correlation at large angles. Quantifying the degree to which this feature in the temperature…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Andrew P. Hearin , Cameron Gibelyou , Andrew R. Zentner

Dark matter comprised of axion-like particles (ALPs) generated by the realignment mechanism in the post-inflationary scenario leads to primordial isocurvature fluctuations. The power spectrum of these fluctuations is flat for small wave…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-09 Martin Feix , Steffen Hagstotz , Andreas Pargner , Robert Reischke , Bjoern Malte Schaefer , Thomas Schwetz

We investigate the potential of observations of anisotropies in the cosmic microwave background (CMB) and large-scale structure in the Universe to detect possible modifications of standard inflationary models by physics beyond the Planck…

Astrophysics · Physics 2009-11-10 Oystein Elgaroy , Steen Hannestad

The inflaton field responsible for inflation may not be a canonical fundamental scalar. It is possible that the inflaton is a composite of fermions or it may have a decay width. In these cases the standard procedure for calculating the…

High Energy Physics - Phenomenology · Physics 2009-09-28 Suratna Das , Subhendra Mohanty

Modern cosmology has now emerged as a testing ground for theories beyond the standard model of particle physics. In this paper, we consider quantum fluctuations of the inflaton scalar field on certain noncommutative spacetimes and look for…

Astrophysics · Physics 2009-03-24 Earnest Akofor , A. P. Balachandran , Sang G. Jo , Anosh Joseph , Babar A. Qureshi

It is assumed that the dark energy observed today is frozen as a result of a phase transition involving the source of that energy. Postulating that the dark energy de-coherence which results from this phase transition drives statistical…

Astrophysics · Physics 2009-11-10 James V. Lindesay , H. Pierre Noyes , E. D. Jones

In this paper, we present compelling evidence for the parity asymmetry (a discrete symmetry that is separate from isotropy) in the Cosmic Microwave Background (CMB) map, measured through two-point temperature correlations. This parity…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-07 Enrique Gaztañaga , K. Sravan Kumar

We measure the cosmic microwave background (CMB) power spectrum on angular scales l~30-200 (1-6 degrees) from the QMASK map, which combines the data from the QMAP and Saskatoon experiments. Since the accuracy of recent measurements leftward…

Astrophysics · Physics 2009-10-07 Yongzhong Xu , Max Tegmark , Angelica de Oliveira-Costa

We present a measurement of the angular power spectrum of the cosmic microwave background (CMB) using data from the South Pole Telescope (SPT). The data consist of 790 square degrees of sky observed at 150 GHz during 2008 and 2009. Here we…

We examine the degree to which observations of large-scale cosmic microwave background (CMB) polarization can shed light on the puzzling large-scale power modulation in maps of CMB anisotropy. We consider a phenomenological model in which…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-23 Emory F. Bunn , Qingyang Xue , Haoxuan Zheng