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Related papers: Adiabatic versus Isocurvature Non--Gaussianity

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We study statistical anisotropies generated in the observed two-point function of the cosmic microwave background (CMB) fluctuations if the primordial statistics are non-Gaussian. Focusing on the dipole modulations of the anisotropies, we…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-17 Saroj Adhikari , Anne-Sylvie Deutsch , Sarah Shandera

We present measurements of the dark matter bispectrum in N-body simulations with non-Gaussian initial conditions of the local kind for a large variety of triangular configurations and compare them with predictions from Eulerian Perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Emiliano Sefusatti , Martin Crocce , Vincent Desjacques

We revisit the predictions for the expected Cosmic Microwave Background bispectrum signal from the primary-lensing-Rees-Sciama correlation; we point out that it can be a significant contaminant to the bispectrum signal from primordial…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-09 Anna Mangilli , Licia Verde

This is the second in a series of papers on preheating in inflationary models comprised of multiple scalar fields coupled nonminimally to gravity. In this paper, we work in the rigid-spacetime approximation and consider field trajectories…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-30 Matthew P. DeCross , David I. Kaiser , Anirudh Prabhu , Chanda Prescod-Weinstein , Evangelos I. Sfakianakis

We explore and corroborate, by working out explicit examples, the effectiveness of cross-correlating stochastic gravitational wave background anisotropies with CMB temperature fluctuations as a way to establish the primordial nature of a…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-30 Ameek Malhotra , Ema Dimastrogiovanni , Matteo Fasiello , Maresuke Shiraishi

We show that the shape of the inflationary landscape potential may be constrained by analyzing cosmological data. The quantum fluctuations of fields orthogonal to the inflationary trajectory may have probed the structure of the local…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-18 Xingang Chen , Gonzalo A. Palma , Bruno Scheihing Hitschfeld , Spyros Sypsas

Primordial non-Gaussianity (PNG) is a key probe of the origins of primordial fluctuations in the early universe. It has been shown that multi-tracer measurements of large-scale structure can produce high-precision measurements of PNG.…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-24 R. Henry Liu , Patrick C. Breysse

A first-order phase transition in the early universe can give an observable stochastic gravitational background (SGWB), which will necessarily have primordial anisotropies across the sky. In multi-field inflationary scenarios, these…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Arushi Bodas , Raman Sundrum

Inflationary predictions for the power spectrum of the curvature perturbation have been verified to an excellent degree, leaving many models compatible with observations. In this thesis we studied third-order correlations, that might allow…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 Eleftheria Tzavara

Produced nonlinearly by the enhanced linear cosmological curvature perturbations, the scalar-induced gravitational waves (SIGWs) can serve as a potentially powerful probe of primordial non-Gaussianity (PNG) in the early Universe. In this…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Jun-Peng Li , Sai Wang , Zhi-Chao Zhao , Kazunori Kohri

We apply a new method to measure primordial non-Gaussianity, using the cross-correlation between galaxy surveys and the CMB lensing signal to measure galaxy bias on very large scales, where local-type primordial non-Gaussianity predicts a…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-06 Tommaso Giannantonio , Will J. Percival

We use simulated maps of the cosmic microwave background anisotropy to quantify the ability of different statistical tests to discriminate between Gaussian and non-Gaussian models. Despite the central limit theorem on large angular scales,…

Astrophysics · Physics 2009-10-31 Nicholas G. Phillips , A. Kogut

We analyse the large-scale angular clustering of quasars in the \gaia-\unwise quasar catalog, \quaia, and their cross-correlation with maps of the lensing convergence of the Cosmic Microwave Background (CMB), to constrain the level of…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Giulio Fabbian , David Alonso , Kate Storey-Fisher , Thomas Cornish

Since the first limit on the (local) primordial non-Gaussianity parameter, fNL, was obtained from COBE data in 2002, observations of the CMB have been playing a central role in constraining the amplitudes of various forms of non-Gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Eiichiro Komatsu

Thanks to the rapid progress in precision cosmology in the last few years, we now have access to physical observables that may constrain the theory of inflation through the non-Gaussianity (NG) signatures in the cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-19 Xinghai Zhao , Yuexing Li , Sarah Shandera , Donghui Jeong

We measure the skewness power spectrum of the Cosmic Microwave Background (CMB) anisotropies optimized for a detection of the secondary bispectrum generated by the correlation of the CMB lensing potential with integrated Sachs-Wolfe effect…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Erminia Calabrese , Joseph Smidt , Alexandre Amblard , Asantha Cooray , Alessandro Melchiorri , Paolo Serra , Alan Heavens , Dipak Munshi

We study cosmological perturbations in the case that present-day matter consists of a mixture of inflaton and curvaton decay products. We calculate how the curvaton perturbations are transferred to its decay products in the general case…

Astrophysics · Physics 2007-05-23 Francesc Ferrer , Syksy Rasanen , Jussi Valiviita

The bispectrum of the cosmic microwave background (CMB) generated by a correlation between a time-dependent gravitational potential and the weak gravitational lensing effect provides a direct measurement of the influence of dark energy on…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Veronika Junk , Eiichiro Komatsu

Under the presence of anisotropic sources in the inflationary era, the trispectrum of the primordial curvature perturbation has a very specific angular dependence between each wavevector that is distinguishable from the one encountered when…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Maresuke Shiraishi , Nicola Bartolo , Michele Liguori

Since a positive future detection of non-linearity in the cosmic microwave background anisotropy pattern might allow to descriminate among different mechanisms giving rise to cosmological adiabatic perturbations, we study the evolution of…

High Energy Physics - Phenomenology · Physics 2010-02-10 N. Bartolo , S. Matarrese , A. Riotto
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