English
Related papers

Related papers: Primordial non-Gaussianity in density fluctuations

200 papers

We present forecast results for constraining the primordial non-Gaussianity from photometric surveys through a large-scale enhancement of the galaxy clustering amplitude. In photometric surveys, the distribution of observed galaxies at high…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Toshiya Namikawa , Tomohiro Okamura , Atsushi Taruya

I investigate non-Gaussian signatures in the context of tachyacoustic cosmology, that is, a noninflationary model with superluminal speed of sound. I calculate the full non-Gaussian amplitude $\mathcal{A}$, its size $f_{\rm NL}$, and…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Dennis Bessada

The formalism that describes the non-linear growth of the angular momentum L of protostructures from tidal torques in a Friedmann Universe, as developed in a previous paper, is extended to include non-Gaussian initial conditions. We…

Astrophysics · Physics 2015-06-24 Paolo Catelan , Tom Theuns

Local-type primordial non-gaussianity generates a distinctive term in the clustering of tracers of large-scale structure, behaving as $k^{-2}$ at small wavenumbers $k$. In order to use this signal in a sample of galaxies to measure the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Neal Dalal , Will J. Percival

We analyse the large--scale velocity field obtained by N--body simulations of cold dark matter (CDM) models with non--Gaussian primordial density fluctuations, considering models with both positive and negative primordial skewness in the…

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

Primordial non-Gaussianity has emerged as one of the most promising probes of the inflationary epoch. While the cosmic microwave background and large-scale halo bias currently provide the most stringent constraints on the non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Marilena LoVerde , Kendrick M. Smith

We consider contributions to non-Gaussianity of the Cosmic Microwave Background (CMB) from remnants of post-inflationary phase transitions in the very early universe. Such signatures can optimistically be used to discover evidence of new…

Astrophysics · Physics 2010-01-11 Alessandra Silvestri , Mark Trodden

We present simulations of the Cosmic Microwave Background Radiation (CMBR) power spectrum for a class of mixed, non-Gaussian, primordial random fields. We assume a skew positive mixed model with adiabatic inflation perturbations plus…

Astrophysics · Physics 2009-11-10 Ana Paula Andrade , Carlos Alexandre Wuensche , Andre Luiz B. Ribeiro

Primordial non-Gaussianity (PNG) is a signature of fundamental physics in the early universe that is probed by cosmological observations. It is well known that the local type of PNG generates a strong signal in the two-point function of…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 James M. Sullivan , Uros Seljak

An attractive and simple hypothesis for the formation of large-scale structure is that it developed by gravitational instability from primordial fluctuations with an initially Gaussian probability distribution. Non-linear gravitational…

Astrophysics · Physics 2015-06-24 Ewa Luiza Lokas , Roman Juszkiewicz , David Weinberg , Francois Bouchet

We study non-Gaussianity, the spectral index of primordial scalar fluctuations and tensor modes in models where fluctuations from the inflaton and the curvaton can both contribute to the present cosmic density fluctuations. Even though…

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

We use the delta N -formalism to investigate the non-Gaussianity of the primordial curvature perturbation in the curvaton scenario for the origin of structure. We numerically calculate the full probability distribution function allowing for…

Astrophysics · Physics 2010-04-06 Misao Sasaki , Jussi Valiviita , David Wands

A basic ingredient to understand large scale fluctuations in our present day Universe is the initial conditions. Using N-body simulations, we compare the clustering that arises from Gaussian and non-Gaussian initial conditions. The latter…

Astrophysics · Physics 2009-10-28 E. Gaztanaga , P. Mahonen

Primordial non-Gaussianity is predicted by various inflationary models, and N-body simulations are a crucial tool for studying its imprints on large-scale structure. In this work, we present \texttt{GENGARS} ( GEnerator of Non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-05 Emanuele Fondi , Licia Verde , Marco Baldi , William Coulton , Francisco Villaescusa-Navarro , Benjamin Dan Wandelt

Tighter constraints on measurements of primordial non-Gaussianity will allow the differentiation of inflationary scenarios. The cosmic microwave background bispectrum-the standard method of measuring the local non-Gaussianity-is limited by…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-15 Zahra Gomes , Stefano Camera , Matt J. Jarvis , Catherine Hale , José Fonseca

Primordial non-Gaussianity of local type is known to produce a scale-dependent contribution to the galaxy bias. Several classes of multi-field inflationary models predict non-Gaussian bias which is stochastic, in the sense that dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Simone Ferraro , Kendrick M. Smith

Non-linear evolution of cosmological energy density fluctuations triggers deviations from Gaussianity in the temperature distribution of the cosmic microwave background. A method to estimate these deviations is proposed. N-body simulations…

Astrophysics · Physics 2009-11-07 A. M. Aliaga , V. Quilis , J. V. Arnau , D. Saez

Primordial non-Gaussianities (PNGs) are signatures in the density field that encode particle physics processes from the inflationary epoch. Such signatures have been extensively studied using the Cosmic Microwave Background, through…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-01 Dhayaa Anbajagane , Chihway Chang , Hayden Lee , Marco Gatti

The observed abundance of high-redshift galaxies and clusters contains precious information about the properties of the initial perturbations. We present a method to compute analytically the number density of objects as a function of mass…

Astrophysics · Physics 2011-05-05 Sabino Matarrese , Licia Verde , Raul Jimenez

We study how primordial non-Gaussianity affects the pairwise velocity probability density function (PDF) using an analytical model and cosmological N-body simulations. We adopt the local type non-Gaussian models characterized by f_{nl}, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Tsz Yan Lam , Takahiro Nishimichi , Naoki Yoshida