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We present two novel methods for the estimation of the angular power spectrum of cosmic microwave background (CMB) anisotropies. We assume an absolute CMB experiment with arbitrary asymmetric beams and arbitrary sky coverage. The methods…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Elina Keihänen , Kimmo Kiiveri , Hannu Kurki-Suonio , Martin Reinecke

These lecture notes comprise an informal but pedagogical introduction to the well established physics and phenomenology of the cosmic microwave background (CMB) between big bang nucleosynthesis and recombination. The dominant properties of…

Astrophysics · Physics 2008-02-26 Wayne Hu

It has been argued that the power spectrum of the anisotropies in the Cosmic Microwave Background (CMB) may be effectively degenerate, namely that the observable spectrum does not determine a unique set of cosmological parameters. We…

Astrophysics · Physics 2015-06-24 R. Benton Metcalf , Joseph Silk

First results of a Cosmic Microwave Background (CMB) anisotropy experiment conducted at the Observatorio del Teide (Tenerife, Spain) are presented. The instrument is a four channel (3.1, 2.1, 1.3 and 1.1 mm) $^3$He bolometer system coupled…

Measuring the deviation from scale invariance of the primordial power spectrum is a critical test of inflation. In this paper we reconstruct the shape of the primordial power spectrum of curvature perturbations from the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-01 Zong-Kuan Guo , Dominik J. Schwarz , Yuan-Zhong Zhang

Although the cosmic microwave background (CMB) is largely understood to be homogeneous and isotropic, the CMB angular power spectra present anomalies that seem to break down parity symmetry at large angular scales. We argue that the…

General Relativity and Quantum Cosmology · Physics 2024-11-12 K. Sravan Kumar , João Marto

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

We compute the tensor CMB anisotropy power spectrum for singular and non-singular instantons describing the beginning of an open universe according to the Euclidean no boundary proposal. Singular instantons occur generically, whereas…

Astrophysics · Physics 2009-12-30 Steven Gratton , Thomas Hertog , Neil Turok

We investigate the imprint of nonlinear matter condensations on the Cosmic Microwave Background (CMB) in an $\Omega=1$, Cold Dark Matter (CDM) model universe. Temperature anisotropies are obtained by numerically evolving matter…

Astrophysics · Physics 2016-08-30 Robin Tuluie , Pablo Laguna

In the inflationary scenarios suggested by string theory, the vacuum fluctuations of the electromagnetic field can be amplified by the time-evolution of the dilaton background, and can grow large enough to explain both the origin of the…

Astrophysics · Physics 2010-01-06 M. Gasperini , M. Giovannini , G. Veneziano

Precision measurements of anisotropies in the cosmic microwave background and of the clustering of large-scale structure have supposedly confirmed that the primordial density perturbation has a (nearly) scale-invariant spectrum. However…

High Energy Physics - Phenomenology · Physics 2011-02-16 Subir Sarkar

The cosmic microwave background (CMB), carrying the inhomogeneous information of the very early universe, is of great significance for understanding the origin and evolution of our universe. However, observational CMB maps contain serious…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-12 Guo-Jian Wang , Hong-Liang Shi , Ye-Peng Yan , Jun-Qing Xia , Yan-Yun Zhao , Si-Yu Li , Jun-Feng Li

We use weighted mean and median statistics techniques to combine individual cosmic microwave background (CMB) anisotropy detections and determine binned, multipole-space, CMB anisotropy power spectra. The resultant power spectra are peaked.…

The thermal evolution of the cosmic gas decoupled from that of the cosmic microwave background (CMB) at a redshift z~200. Afterwards and before the first stars had formed, the cosmic neutral hydrogen absorbed the CMB flux at its resonant…

Astrophysics · Physics 2010-04-06 Abraham Loeb , Matias Zaldarriaga

To minimize instrumentally induced systematic errors, cosmic microwave background (CMB) anisotropy experiments measure temperature differences across the sky using paires of horn antennas, temperature map is recovered from temperature…

Astrophysics · Physics 2009-08-30 Hao Liu , Ti-Pei Li

We compute the fully non-linear Cosmic Microwave Background (CMB) anisotropies on scales larger than the horizon at last-scattering in terms of only the curvature perturbation, providing a generalization of the linear Sachs-Wolfe effect at…

Astrophysics · Physics 2009-11-13 N. Bartolo , S. Matarrese , A. Riotto

We compare the latest observations of Cosmic Microwave Background (CMB) Anisotropies with the theoretical predictions of the standard scenario of structure formation. Assuming a primordial power spectrum of adiabatic perturbations we found…

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

We investigate early dark energy models in the context of the lensing anomaly by considering two different Cosmic Microwave Background (CMB) datasets: a complete Planck, and a second one primarily based on SPTPol and Planck temperature…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-20 Balakrishna S. Haridasu , Hasti Khoraminezhad , Matteo Viel

Since the measurements of COBE/FIRAS in the mid-90's we know that the energy spectrum of the cosmic microwave background (CMB) is extremely close to that of a perfect blackbody at an average temperature T0~2.726K. However, a number of…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-11 Jens Chluba

The distribution of the polarization of the Cosmic Microwave Background (CMB) in the sky is determined by the hypothesis of random Gaussian distribution of the primordial density perturbations. This hypotheses is well motivated by the…

Astrophysics · Physics 2009-10-30 P. D. Naselsky , D. I. Novikov
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