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Related papers: Suppressed Non-Gaussianity in the Curvaton Model

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In our previous work the nonlinearity parameter f_NL, which characterizes nongaussianity in the cosmic microwave background, was estimated for a class of inflationary models based on nonlocal field theory. These models include p-adic…

High Energy Physics - Theory · Physics 2009-08-25 Neil Barnaby , James M. Cline

The viscous inhomogeneities of a relativistic plasma determine a further class of entropic modes whose amplitude must be sufficiently small since curvature perturbations are observed to be predominantly adiabatic and Gaussian over large…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 Massimo Giovannini

We analyze the curvaton scenario in the context of supersymmety. Supersymmetric theories contain many scalars, and therefore many curvaton candidates. To obtain a scale invariant perturbation spectrum, the curvaton mass should be small…

High Energy Physics - Phenomenology · Physics 2014-11-17 Marieke Postma

We study the effect of primordial non-Gaussianity on the development of large-scale cosmic structure using high-resolution N-body simulations. In particular, we focus on the topological properties of the "cosmic web", quantitatively…

As a nonrelativistic particle constrained to remain on an $N-1$ ($N\geq 2$) dimensional hypersurface embedded in an $N$ dimensional Euclidean space, two different components $p_{i}$ and $p_{j}$ ($i,j=1,2,3,...N$) of the Cartesian momentum…

General Physics · Physics 2019-09-02 Q. H. Liu , X. Yang , Z. Li

We study cuscuton inflation for the models where the potential of the cuscuton takes quadratic and exponential forms. We find that for the quadratic potential, a scalar spectral index $n_s$ is not affected by cuscuton at the leading order…

General Relativity and Quantum Cosmology · Physics 2023-05-23 Phongpichit Channuie , Khamphee Karwan , Jakkrit Sangtawee

We show that modifications of Einstein gravity during inflation could leave potentially measurable imprints on cosmological observables in the form of non-Gaussian perturbations. This is due to the fact that these modifications appear in…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-22 Nicola Bartolo , Dario Cannone , Raul Jimenez , Sabino Matarrese , Licia Verde

We compute the super-Hubble evolution of non-Gaussianity of primordial curvature perturbations in two-field inflation models by employing two formalisms: delta N and covariant formalisms. Although two formalisms treat the evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Yuki Watanabe

Single field inflationary models predict nearly Gaussian initial conditions and hence a detection of non-Gaussianity would be a signature of the more complex inflationary scenarios. In this paper we study the effect on the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Dmitriy Tseliakhovich , Christopher Hirata , Anze Slosar

Gravity is a non-linear theory, and hence, barring cancellations, the initial super-horizon perturbations produced by inflation must contain some minimum amount of mode coupling, or primordial non-Gaussianity. In single-field slow-roll…

High Energy Physics - Theory · Physics 2017-01-11 Giovanni Cabass , Enrico Pajer , Fabian Schmidt

Developing on the ideas of (section 4 of) [1] and [2] and using the formalisms of [3] and [4], after inclusion of perturbative and non-perturbative alpha' corrections to the Kaehler potential and (D1- and D3-) instanton generated…

High Energy Physics - Theory · Physics 2009-12-11 Aalok Misra , Pramod Shukla

We use cosmological N-body simulations to investigate whether measurements of the moments of large-scale structure can yield constraints on primordial non-Gaussianity. We measure the variance, skewness, and kurtosis of the evolved density…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-24 Qingqing Mao , Andreas A. Berlind , Cameron K. McBride , Robert J. Scherrer , Roman Scoccimarro , Marc Manera

We show, both analytically and numerically, that non-Gaussian tails in the probability density function of curvature perturbations arise in ultra-slow-roll inflation from the $\delta N$ formalism, without invoking stochastic inflation.…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-12 Guillermo Ballesteros , Thomas Konstandin , Alejandro Pérez Rodríguez , Mathias Pierre , Julián Rey

We compute non-Gaussianities in N-flation, a string motivated model of assisted inflation with quadratic, separable potentials and masses given by the Marcenko-Pastur distribution. After estimating parameters characterizing the bi- and…

High Energy Physics - Theory · Physics 2010-10-27 Diana Battefeld , Thorsten Battefeld

Using the quantum information picture to describe the early universe as a time dependent quantum density matrix, with time playing the role of a stochastic variable, we compute the non-gaussian features in the distribution of primordial…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-19 Cesar Gomez , Raul Jimenez

The quantum theory of the electromagnetic field enables the description of multiphoton states exhibiting nonclassical statistical properties, often reflected in non-Gaussian phase-space distributions. While non-Gaussianity alone does not…

The thermal non-Gaussianity in Near-Milne universe is investigated in this letter. Through classifying thermal fluctuations into two types, one characterized by a phase transition and the other without phase transition, we show that for…

High Energy Physics - Theory · Physics 2010-01-31 Jian-Pin Wu , Yi Ling

We analyze multi-field inflationary systems which yield strongly scale dependent non-Gaussianity with a shape that is very close to the local shape. As in usual multi-field models, the non-Gaussianity arises from the non-linear transfer of…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-27 Jason Kumar , Louis Leblond , Arvind Rajaraman

The non-Gaussian normal diffusion, i.e., the probability distribution function (PDF) is non-Gaussian but the mean squared displacement (MSD) depends on time linearly, has been observed in particle motions. Here we show by numerical…

Disordered Systems and Neural Networks · Physics 2016-04-06 Jianjin Wang , Yong Zhang , Hong Zhao

The dynamics of a quantum system with internal degrees of freedom undergoing spontaneous collapse in the position basis are analysed; e.g., neutral mesons or neutrinos. Surprisingly, the value of the Heaviside function $\theta(x)$ at $x=0$…

Quantum Physics · Physics 2016-02-18 K. Simonov , B. C. Hiesmayr
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