English
Related papers

Related papers: The Void Abundance with Non-Gaussian Primordial Pe…

200 papers

We develop a non-perturbative formalism for scalar metric fluctuations from a 5D extended version of general relativity in vacuum. In this work we concentrate our efforts on calculations valid on large cosmological scales, which are the…

General Relativity and Quantum Cosmology · Physics 2015-06-15 José Edgar Madriz Aguilar , Luz Marina Reyes , Claudia Moreno , Mauricio Bellini

We perturbatively study the effect of non-Gaussianities on the mass fraction of primordial black holes (PBHs) at the time of formation by systematically taking its effect into account in the one-point probability distribution function of…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-02 Takahiko Matsubara , Misao Sasaki

The theory and methodology is developed to compute the bispectrum in warm inflation, leading to results for the non-linearity parameter and the shape of the bispectrum. Particular attention is paid to the study of the bispectrum in the…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-10 Mar Bastero-Gil , Arjun Berera , Ian G. Moss , Rudnei O. Ramos

We study nonlinear cosmological perturbations and their possible non-Gaussian character in an extended non-minimal inflation where gravity is coupled non-minimally to both the scalar field and its derivatives. By expansion of the action up…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Raheleh Shojaee , Kourosh Nozari , Farhad Darabi

A detection of primordial non-Gaussianity could transform our understanding of the fundamental theory of inflation. The precision promised by upcoming CMB and large-scale structure surveys raises a natural question: if a detection given a…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-04 Joyce Byun , Rachel Bean

While usually cosmological initial conditions are assumed to be Gaussian, inflationary theories can predict a certain amount of primordial non-Gaussianity which can have an impact on the statistical properties of the lensing observables. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 F. Pace , L. Moscardini , M. Bartelmann , E. Branchini , K. Dolag , M. Grossi , S. Matarrese

Skewness and non-Gaussian behavior are essential features of the distribution of short-scale velocity increments in isotropic turbulent flows. Yet, although the skewness has been generally linked to time-reversal symmetry breaking and…

The new Planck constraints on the local bispectrum parameter fnl are about 10^5 times tighter than the current constraints on the trispectrum parameter gnl, which means that the allowed numerical values of the second and third order terms…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Christian T. Byrnes , Sami Nurmi , Gianmassimo Tasinato , David Wands

We demonstrate that local, scale-dependent non-Gaussianity can generate cosmic variance uncertainty in the observed spectral index of primordial curvature perturbations. In a universe much larger than our current Hubble volume, locally…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Joseph Bramante , Jason Kumar , Elliot Nelson , Sarah Shandera

We suppose that a vector field perturbation causes part of the primordial curvature perturbation. The non-Gaussianity parameter fNL is then, in general, statistically anisotropic. We calculate its form and magnitude in the curvaton scenario…

Astrophysics · Physics 2009-09-02 Mindaugas Karciauskas , Konstantinos Dimopoulos , David H. Lyth

Future galaxy surveys promise to probe local primordial non-Gaussianity at unprecedented precision, $\sigma(f_{\rm NL}) \lesssim 1$. We study the implications for multifield inflation by considering spectator models, where inflation is…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Roland de Putter , Jérôme Gleyzes , Olivier Doré

We investigate the possibility of constraining primordial non-Gaussianity using the 3D bispectrum of Ly-alpha forest. The strength of the quadratic non-Gaussian correction to an otherwise Gaussian primordial gravitational field is assumed…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-19 Dhiraj Kumar Hazra , Tapomoy Guha Sarkar

The primordial non-Gaussian parameter fNL has been shown to be scale-dependent in several models of inflation with a variable speed of sound. Starting from a simple ansatz for a scale-dependent amplitude of the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 Emiliano Sefusatti , Michele Liguori , Amit P. S. Yadav , Mark G. Jackson , Enrico Pajer

In this article, we show that a stochastic form of scale-dependent halo bias arises in multi-source inflationary models, where multiple fields determine the initial curvature perturbation. We derive this effect for general non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-14 Daniel Baumann , Simone Ferraro , Daniel Green , Kendrick M. Smith

We investigate the possibility to detect primordial non-Gaussianity by analysing the bulk of the probability distribution function (PDF) of late-time cosmic density fluctuations. For this purpose we devise a new method to predict the impact…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-02 Oliver Friedrich , Cora Uhlemann , Francisco Villaescusa-Navarro , Tobias Baldauf , Marc Manera , Takahiro Nishimichi

In [1], a most general higher curvature non-local gravity action was derived that admits a particular $R^2$-like inflationary solution predicting the spectral index of primordial scalar perturbations $n_s(N)\approx 1-\frac{2}{N}$, where $N$…

High Energy Physics - Theory · Physics 2023-07-18 Alexey S. Koshelev , K. Sravan Kumar , Alexei A. Starobinsky

In a recently published article, we quantified the impact of primordial non-Gaussianity on the probability of giant-arc formation. In that work, we focused on the local form of non-Gaussianity and found that it can have only a modest effect…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-06 Anson D'Aloisio , Priyamvada Natarajan

In this work, we present a method for implementing the $\delta N$ formalism to study the primordial non-Gaussianity produced in multiple three-form field inflation. Using a dual description relating three-form fields to noncanonical scalar…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 K. Sravan Kumar , David J. Mulryne , Nelson J. Nunes , João Marto , Paulo Vargas Moniz

Preheating can convert superhorizon fluctuations of light scalar fields present at the end of inflation into observable density perturbations. We show in detail how lattice field theory simulations and the separate universes approximation…

Astrophysics · Physics 2008-09-30 Alex Chambers , Arttu Rajantie