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There are evidences that the cosmic microwave background (CMB) large-angle anomalies imply a departure from statistical isotropy and hence from the standard cosmological model. We propose a LCDM model extension whose dark energy component…

Astrophysics · Physics 2008-11-26 Davi C. Rodrigues

The physics of the origin and evolution of CMB anisotropies is described. I explain the idea and status of cosmic parameter estimation and follow it up with critical comments on its dependence on model assumptions and initial conditions.

Astrophysics · Physics 2021-04-28 Ruth Durrer

Cosmic microwave background (CMB) observations provide in principle a high-precision test of models which are motivated by M theory. We set out the framework of a program to compute the tensor anisotropies in the CMB that are generated in…

Astrophysics · Physics 2009-11-07 Bernard Leong , Anthony Challinor , Roy Maartens , Anthony Lasenby

We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N)-theories. We point out a problem…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Elisa Fenu , Daniel G. Figueroa , Ruth Durrer , Juan Garcia-Bellido , Martin Kunz

We consider an inverse problem for the linear one-dimensional wave equation with variable coefficients consisting in determining an unknown source term from a boundary observation. A method to obtain approximations of this inverse problem…

Numerical Analysis · Mathematics 2025-01-22 Carlos Castro , Sorin Micu

Spatially fluctuating primordial magnetic fields (PMFs) inhomogeneously reheat the Universe when they dissipate deep inside the horizon before recombination. Such an energy injection turns into an additional photon temperature perturbation.…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-28 Shohei Saga , Atsuhisa Ota , Hiroyuki Tashiro , Shuichiro Yokoyama

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

The cosmic microwave background (CMB) is a significant source of knowledge about the origin and evolution of our universe. However, observations of the CMB are contaminated by foreground emissions, obscuring the CMB signal and reducing its…

Machine Learning · Computer Science 2023-02-27 Jadie Adams , Steven Lu , Krzysztof M. Gorski , Graca Rocha , Kiri L. Wagstaff

For the first time, we develop in this paper the globally convergent convexification numerical method for a Coefficient Inverse Problem for the 3D Helmholtz equation for the case when the backscattering data are generated by a point source…

Numerical Analysis · Mathematics 2020-02-14 Vo Anh Khoa , Michael Victor Klibanov , Loc Hoang Nguyen

In this article, we study the one-dimensional inverse problem of determining the memory kernel by the integral overdetermination condition for the direct problem of finding the velocity potential and the displacement of boundary points. A…

Analysis of PDEs · Mathematics 2026-02-24 Zhanna D. Totieva , Kush Kinra , Manil T. Mohan

Most of the cosmological information extracted from the CMB has been obtained through the power spectrum, however there is much more to be learnt from the statistical distribution of the temperature random field. We review some recent…

Astrophysics · Physics 2015-06-24 Enrique Martinez-Gonzalez

We investigate a statistical anisotropy on the Cosmic Microwave Background (CMB) bispectrum, which can be generated from the primordial non-Gaussianity induced by quantum fluctuations of a vector field. We find new configurations in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-03 Maresuke Shiraishi , Shuichiro Yokoyama

We consider the inverse problem of recovering the optical properties of a highly-scattering medium from acousto-optic measurements. Using such measurements, we show that the scattering and absorption coefficients of the radiative transport…

Analysis of PDEs · Mathematics 2016-09-27 Francis J Chung , John C Schotland

Weak gravitational lensing by the intervening large-scale structure (LSS) of the Universe is the leading non-linear effect on the anisotropies of the cosmic microwave background (CMB). The integrated line-of-sight mass that causes the…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-26 Alba Kalaja , Giorgio Orlando , Aleksandr Bowkis , Anthony Challinor , P. Daniel Meerburg , Toshiya Namikawa

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

Cosmic microwave background (CMB) anisotropies and density fluctuations are calculated for flat cold dark matter (CDM) models with a wide range of parameters, i.e., $\Omega_0, h$ and $\Omega_B$ for both standard recombination and various…

Astrophysics · Physics 2009-10-22 Naoshi Sugiyama

We study the Cosmic Microwave Background (CMB) anisotropies produced by cosine-type quintessence models. In our analysis, effects of the adiabatic and isocurvature fluctuations are both taken into account. For purely adiabatic fluctuations…

Astrophysics · Physics 2007-05-23 Tomo Takahashi

The cosmic microwave background (CMB), the relic radiation from the early Universe, offers a unique window into both primordial conditions and the intervening large-scale structure (LSS) it traverses. Interactions between CMB photons and…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-24 Federico Bianchini , Abhishek S. Maniyar

Spectral distortions and anisotropies of the CMB provide independent and complementary probes to study energy injection processes in the early universe. Here we discuss the synergy between these observables, and show the promising future of…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-04 Matteo Lucca , Nils Schöneberg , Deanna C. Hooper , Julien Lesgourgues , Jens Chluba

Cosmic microwave background (CMB) anisotropies probe the primordial density field at the edge of the observable Universe. There is a limiting precision (``cosmic variance'') with which anisotropies can determine the amplitude of primordial…

Astrophysics · Physics 2016-08-25 Marc Kamionkowski , Abraham Loeb
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