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Related papers: Constraining Running Non-Gaussianity

200 papers

We make a comprehensive investigation of the observational effect of the inflation consistency relation. We focus on the general single-field inflation model with the consistency relation $r=-8c_s n_t$, and investigate the observational…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Cheng Cheng , Qing-Guo Huang , Xiao-Dong Li , Yin-Zhe Ma

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

We present an analysis of the Minkowski Functionals (MFs) describing the WMAP three-year temperature maps to place limits on possible levels of primordial non-Gaussianity. In particular, we apply perturbative formulae for the MFs to give…

We study the cosmic variance limit on constraining primordial non-Gaussianity for a variety of theory-motivated shapes. We consider general arguments for 2D and 3D surveys, with a particular emphasis on the CMB. A scale-invariant $N$-point…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-11 Alba Kalaja , P. Daniel Meerburg , Guilherme L. Pimentel , William R. Coulton

We investigate non-Gaussianity in general single field models without assuming slow-roll conditions or the exact scale-invariance of the scalar power spectrum. The models considered include general single field inflation (e.g. DBI and…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-13 Johannes Noller , Joao Magueijo

Two of the most commonly used tools to constrain the primordial non-Gaussianity are the bispectrum and the Minkowski functionals of CMB temperature anisotropies. These two measures of non-Gaussianity in principle provide distinct (though…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-26 Wenjuan Fang , Adam Becker , Dragan Huterer , Eugene A. Lim

If the primordial fluctuations are non-Gaussian, then this non-Gaussianity will be apparent in the cosmic microwave background (CMB) sky. With their sensitive all-sky observation, MAP and Planck satellites should be able to detect weak…

Astrophysics · Physics 2009-07-09 Eiichiro Komatsu , David N. Spergel

Any hint of non-gaussianity in the cosmological initial conditions will provide us with a unique window into the physics of early universe. We show that the impact of a small local primordial non-gaussianity (generated on super-horizon…

Astrophysics · Physics 2008-12-18 Niayesh Afshordi , Andrew J. Tolley

We show how to build a curvaton inflationary model motivated by scale-dependent non-Gaussianities of cosmological perturbations. In particular, we study the change of sign in the $f_{NL}$ parameter as a function of the curvaton field value…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 L. F. Guimarães , F. T. Falciano

Recently we studied inflation models in which the inflaton potential is characterized by an underlying approximate global symmetry. In the first work we pointed out that in such a model curvature perturbations are generated after the end of…

Astrophysics · Physics 2008-11-26 Edward W. Kolb , Antonio Riotto , Alberto Vallinotto

In this paper we present forecasts of the contamination on different shapes of the primordial non-Gaussianity fnl parameter -- detectable on future Cosmic Microwave Background (CMB) high--resolution anisotropy maps -- produced by unresolved…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 A. Curto , M. Tucci , J. Gonzalez-Nuevo , L. Toffolatti , E. Martinez-Gonzalez , F. Argueso , A. Lapi , M. Lopez-Caniego

Current measurements of the temperature and polarization anisotropy power spectra of the Cosmic Microwave Background (CMB) seem to indicate that the naive expectation for the slow-roll hierarchy within the most simple inflationary paradigm…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-10 Stefano Gariazzo , Olga Mena , Victor Miralles , Héctor Ramírez , Lotfi Boubekeur

The late-time effect of primordial non-Gaussianity offers a window into the physics of inflation and the very early Universe. In this work we study the consequences of a particular class of primordial non-Gaussianity that is fully…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 G. A. Peña , G. N. Candlish

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 investigate the scale-dependence of f_NL in the self-interacting curvaton model. We show that the scale-dependence, encoded in the spectral index n_{f_NL}, can be observable by future cosmic microwave background observations, such as…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Christian T. Byrnes , Kari Enqvist , Tomo Takahashi

We explore a plausible mechanism that the hemispherical power asymmetry in the CMB is produced by the spatial variation of the primordial sound speed parameter. We suggest that in a generalized approach of the $\delta N$ formalism the local…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-11 Dong-Gang Wang , Yi-Fu Cai , Wen Zhao , Yang Zhang

In the pursuit of primordial non-Gaussianities, we hope to access smaller scales across larger comoving volumes. At low redshift, the search for primordial non-Gaussianities is hindered by gravitational collapse, to which we often associate…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 Thomas Flöss , Matteo Biagetti , P. Daniel Meerburg

Focusing on the local type primordial non-Gaussianities, we study the bispectrum and trispectrum during a non-minimal slow-roll inflation. We use the so-called $\delta N$ formalism to investigate the super-horizon evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-28 Kosar Asadi , Kourosh Nozari

We forecast the constraints on single-field inflation from the bispectrum of future high-redshift surveys such as MegaMapper. Considering non-local primordial non-Gaussianity (NLPNG), we find that current methods will yield constraints of…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-06 Giovanni Cabass , Mikhail M. Ivanov , Oliver H. E. Philcox , Marko Simonovic , Matias Zaldarriaga

The most direct probe of non-Gaussian initial conditions has come from bispectrum measurements of temperature fluctuations in the Cosmic Microwave Background and of the matter and galaxy distribution at large scales. Such bispectrum…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Liguori , E. Sefusatti , J. R. Fergusson , E. P. S. Shellard