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Related papers: Primordial non-Gaussianity in density fluctuations

200 papers

The simplest models of inflation predict small non-gaussianities and a featureless power spectrum. However, there exist a large number of well-motivated theoretical scenarios in which large non-gaussianties could be generated. In general,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-11 Stefano Gariazzo , Laura Lopez-Honorez , Olga Mena

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

While large scale primordial non-Gaussianity is strongly constrained by present-day data, there are no such constraints at Mpc scales. Here we investigate the effect of significant small-scale primordial non-Gaussianity on structure…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-25 Clément Stahl , Thomas Montandon , Benoit Famaey , Oliver Hahn , Rodrigo Ibata

We investigate non-Gaussianity in the modulated reheating scenario where fluctuations of the decay rate of the inflaton generate adiabatic perturbations, paying particular attention to the non-linearity parameters $f_{\rm NL}, \tau_{\rm…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Teruaki Suyama , Tomo Takahashi , Masahide Yamaguchi

We investigate primordial non-Gaussianity and dark matter isocurvature fluctuations in the modulated reheating and the curvaton scenarios. In these scenarios, large non-Gaussianity can be generated, on the other hand, depending on how dark…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Tomo Takahashi , Masahide Yamaguchi , Shuichiro Yokoyama

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

In this work we study the properties of the mass density field in the non-Gaussian world models simulated by Grossi et al. 2007. In particular we focus on the one-point density probability distribution function of the mass density field in…

Astrophysics · Physics 2010-03-26 M. Grossi , E. Branchini , K. Dolag , S. Matarrese , L. Moscardini

We investigate the effects of non-Gaussianity in the primordial density field on the reionization history. We rely on a semi-analytic method to describe the processes acting on the intergalactic medium (IGM), relating the distribution of…

Astrophysics · Physics 2010-03-26 D. Crociani , L. Moscardini , M. Viel , S. Matarrese

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

Primordial non-Gaussianity is one of the most powerful probes of the inflationary epoch. The particle spectrum relevant to inflation, including masses and spins, is encoded in the precise form of statistical correlations of the adiabatic…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Eugene Chen , Daniel Green , Vincent S. H. Lee

We study the cosmological information contained in the Minkowski Functionals (MFs) of weak gravitational lensing convergence maps. We show that the MFs provide strong constraints on the local type primordial non-Gaussianity parameter f_NL.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Masato Shirasaki , Naoki Yoshida , Takashi Hamana , Takahiro Nishimichi

We address the dual challenge of estimating deviations from Gaussianity arising in models of the Early Universe, whilst retaining information necessary to assess whether a detection of non-Gaussianity is primordial. We do this by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Dipak Munshi , Alan Heavens

We analyze the non--Gaussian primordial fluctuations which are inescapably contributed by scalar fields $\Phi$ with vanishing expectation values, $\langle\Phi\rangle=0$, present during inflation in addition to the inflaton field. For…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Harald F. Muller , Christoph Schmid

Measurements of the non-Gaussianity of the primordial density field have the power to considerably improve our understanding of the physics of inflation. Indeed, if we can increase the precision of current measurements by an order of…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Matteo Tellarini , Ashley J. Ross , Gianmassimo Tasinato , David Wands

Evolution of power spectrum is studied for non-Gaussian models of structure formation. We generalize the dark-matter-approach to these models and find that the evolved spectrum at weakly nonlinear regime is mainly determined by a simple…

Astrophysics · Physics 2009-11-06 Naoki Seto

We investigate the evolution of the skewness of the distribution of density fluctuations in CDM models with both Gaussian and non--Gaussian initial fluctuations. We show that the method proposed by Coles \& Frenk (1991), which uses the…

Astrophysics · Physics 2015-06-24 P. Coles , L. Moscardini , F. Lucchin , S. Matarrese , A. Messina

We simulate CMB maps including non-Gaussianity arising from cubic order perturbations of the primordial gravitational potential, characterized by the non-linearity parameter $g_{NL}$. The maps are used to study the characteristic nature of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Pravabati Chingangbam , Changbom Park

Using $N$-body simulations of cosmological large-scale structure formation, for the first time, we show that the anisotropic primordial non-Gaussianity (PNG) causes a scale-dependent modification, given by $1/k^2$ at small $k$ limit, in the…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Kazuyuki Akitsu , Toshiki Kurita , Takahiro Nishimichi , Masahiro Takada , Satoshi Tanaka

Primordial non-Gaussianities provide an important test of inflationary models. Although the Planck CMB experiment has produced strong limits on non-Gaussianity on scales of clusters, there is still room for considerable non-Gaussianity on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Mélanie Habouzit , Takahiro Nishimichi , Sébastien Peirani , Gary A. Mamon , Joseph Silk , Jacopo Chevallard

We generalize a recently proposed mechanism for the origin of primordial metric perturbations in inflationary models. Quantum fluctuations of light scalar fields during inflation give rise to super-horizon fluctuations of masses and…

Astrophysics · Physics 2010-04-06 Gia Dvali , Andrei Gruzinov , Matias Zaldarriaga