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Related papers: Computing Non- Gaussian Maps of the CMB

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This paper explores a novel application of spherical convolutional neural networks (CNNs) to detect primordial non-Gaussianity in the cosmic microwave background (CMB), a key probe of inflationary dynamics. While effective, traditional…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-28 Jorik Melsen , Thomas Flöss , P. Daniel Meerburg

We study the generation of CMB anisotropies by gravitational lensing on small angular scales. We show these fluctuations are not Gaussian. We prove that the power spectrum of the tail of the CMB anisotropies on small angular scales directly…

Astrophysics · Physics 2009-10-31 Matias Zaldarriaga

Primordial non-Gaussianity arising from inflationary models is a unique probe of non-trivial dynamics of the inflaton field and its interactions with other fields. Often when examining and constraining the scalar non-Gaussianity arising…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-17 Barnali Das , H. V. Ragavendra

We study the degree to which the cosmic microwave background (CMB) can be used to constrain primordial non-Gaussianity involving one tensor and two scalar fluctuations, focusing on the correlation of one polarization $B$ mode with two…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 P. Daniel Meerburg , Joel Meyers , Alex van Engelen , Yacine Ali-Haïmoud

In this article we review the theory of cosmological inflation with a particular focus on the beautiful connection it provides between the physics of the very small and observations of the very large. We explain how quantum mechanical…

Astrophysics · Physics 2010-04-30 Daniel Baumann , Hiranya V. Peiris

A multivariate distribution can be described by a triangular transport map from the target distribution to a simple reference distribution. We propose Bayesian nonparametric inference on the transport map by modeling its components using…

Methodology · Statistics 2023-01-18 Matthias Katzfuss , Florian Schäfer

It is well known that processes of first order phase transitions may have occurred in the inflationary era. If one or more occurred well before the end of inflation, the nucleated bubbles are stretched to large scales and the primordial…

Astrophysics · Physics 2009-10-30 Carlo Baccigalupi

Primordial magnetic fields lead to non-Gaussian signals in the Cosmic Microwave Background (CMB) even at the lowest order, as magnetic stresses, and the temperature anisotropy they induce, depend quadratically on the magnetic field. In…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-03 T. R. Seshadri , Kandaswamy Subramanian

We review the theory of inflationary perturbations. Perturbations at both linear and nonlinear orders are reviewed. We also review a variety of inflation models, emphasizing their signatures on cosmic perturbations.

High Energy Physics - Theory · Physics 2015-06-15 Yi Wang

The presence of astrophysical emissions in microwave observations forces us to perform component separation to extract the Cosmic Microwave Background (CMB) signal. However, even in the most optimistic cases, there are still strongly…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-26 C. Gimeno-Amo , E. Martínez-González , R. B. Barreiro

Bouncing models of cosmology, as they arise e.g. in loop quantum cosmology, can be followed by an inflationary phase and generate close-to-scale-invariant fluctuation spectra as observed in the Cosmic Microwave Background (CMB). However,…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-12 Bartjan van Tent , Paola C. M. Delgado , Ruth Durrer

We generalize the treatment of inflationary perturbations to deal with the non-Markovian colored noise emerging from any realistic approach to stochastic inflation. We provide a calculation of the power-spectrum of the gauge-invariant…

Astrophysics · Physics 2009-11-10 M. Liguori , S. Matarrese , M. Musso , A. Riotto

I summarize recent work on (1) constraining spike-like features in the cosmic microwave background and large scale structure; (2) nonstandard Friedmann equation in stabilized warped 6D brane cosmology, with applications to inflation; and…

Astrophysics · Physics 2008-05-15 James M. Cline

Recent observations opened up a new window on the inflationary model building. As it was firstly reported by the WMAP data, there may be some indications of statistical anisotropy on the CMB map, although the statistical significance of…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-06 Razieh Emami

We introduce the framework of modular inflation with level structure, generalizing the level one theory considered previously to higher levels. We analyze the modular structure of CMB observables in this framework and show that the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-27 Monika Lynker , Rolf Schimmrigk

We propose a framework for separating the information contained in the CMB multipoles, $a_{\ell m}$, into its algebraically independent components. Thus we cleanly separate information pertaining to the power spectrum, non-Gaussianity and…

Astrophysics · Physics 2009-11-10 Kate Land , Joao Magueijo

In this paper we present a new method to estimate a foreground cleaned Cosmic Microwave Background (CMB) map at a resolution of $1^\circ$ by minimizing the non-Gaussian properties of the cleaned map which arise dominantly due to diffuse…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Rajib Saha

We discuss the tests of nonGaussianity in CMB maps using morphological statistics known as Minkowski functionals. As an example we test degree-scale cosmic microwave background (CMB) anisotropy for Gaussianity by studying the \qmask map…

Astrophysics · Physics 2007-05-23 Sergei F. Shandarin , Hume A. Feldman , Yongzhong Xu , Max Tegmark

Recent Planck data show the anomalies of CMB fluctuations on large angular scales, which confirms the early observations by WMAP. We continue studying an inflationary model, in which before the slow roll inflation the universe is in a…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-15 Zhi-Guo Liu , Zong-Kuan Guo , Yun-Song Piao
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