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Related papers: Suppressed Non-Gaussianity in the Curvaton Model

200 papers

I first emphasize the importance of searching for nucleon decay in the context of supersymmetric models. The status of minimal SUSY SU(5) model is reviewed, which can be definitively ruled out by a combination of superKamiokande and LEP-2…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hitoshi Murayama

We show a curvaton model, in which the curvaton has a nonminimal derivative coupling to gravity. Thanks to such a coupling, we find that the scale-invariance of the perturbations can be achieved for arbitrary values of the equation-of-state…

High Energy Physics - Theory · Physics 2015-06-16 Kaixi Feng , Taotao Qiu , Yun-Song Piao

Multiple photon subtraction applied to a displaced phase-averaged coherent state, which is a non-Gaussian classical state, produces conditional states with a non trivial (positive) Glauber-Sudarshan $P$-representation. We theoretically and…

Quantum Physics · Physics 2013-12-02 Stefano Olivares , Alessia Allevi , Maria Bondani

We explore the effect of a cubic correction gnl*phi^3 on the mass function and bias of dark matter haloes extracted from a series of large N-body simulations and compare it to theoretical predictions. Such cubic terms can be motivated in…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Vincent Desjacques , Uros Seljak

Let \Pi\ be a cuspidal automorphic representation for GL(4) over a number field F. We obtain unconditional lower bounds on the number of places at which the Satake parameters are not "too large". In the case of self-dual \Pi\ with…

Number Theory · Mathematics 2013-08-08 Nahid Walji

We study the evolution of non-Gaussianity in multiple-field inflationary models, focusing on three fundamental questions: (a) How is the sign and peak magnitude of the non-linearity parameter fNL related to generic features in the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-07 Joseph Elliston , David Mulryne , David Seery , Reza Tavakol

Primordial non-Gaussianity of the local type induces a strong scale-dependent bias on the clustering of halos in the late-time Universe. This signature is particularly promising to provide constraints on the non-Gaussianity parameter…

A pseudo Nambu-Goldstone boson as curvaton avoids the eta-problem of inflation which plagues most curvaton candidates. We point out that a concrete realization of the curvaton mechanism with a pseudo Nambu-Goldstone boson can be found in…

High Energy Physics - Phenomenology · Physics 2016-09-06 Eung Jin Chun , Konstantinos Dimopoulos , David Lyth

Cosmic inflation provides a mechanism for generating the early density perturbations that seeded the large-scale structures we see today. Primordial non-Gaussianity is among the most promising of few observational tests of physics at this…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-10 Marilena LoVerde , Simone Ferraro , Kendrick M. Smith

We study both oscillating and inflating curvaton scenarios when the curvaton mechanism is caused by a hybrid potential. The source of the curvature perturbation is the inhomogeneous phase transition that causes the modulation of the onset…

High Energy Physics - Phenomenology · Physics 2013-05-30 Konstantinos Dimopoulos , Kazunori Kohri , Tomohiro Matsuda

We present the third-order analytic solution of the matter density fluctuation in the proper-time hypersurface of nonrelativistic matter flows by solving the nonlinear general relativistic equations. The proper-time hypersurface provides a…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-22 Jaiyul Yoo , Jinn-Ouk Gong

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

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

We calculate the higher order moments in a sequence of models where the initial density fluctuations are drawn from a chi^2_nu distribution with a power-law power spectrum. For large values of nu the distribution is approximately gaussian,…

Astrophysics · Physics 2009-10-31 Martin White

Local non-Gaussianity, parametrized by $f_{\rm NL}$, introduces a scale-dependent bias that is strongest at large scales, precisely where General Relativistic (GR) effects also become significant. With future data, it should be possible to…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Marco Bruni , Robert Crittenden , Kazuya Koyama , Roy Maartens , Cyril Pitrou , David Wands

The curvaton reheating mechanism in a non-minimal derivative coupling to gravity for any non-oscillating (NO) model is studied. In this framework, we analyze the energy density during the kinetic epoch and we find that this energy has a…

General Relativity and Quantum Cosmology · Physics 2016-10-05 Ramon Herrera , Joel Saavedra , Cuauhtemoc Campuzano

In curvaton-type models, observable non-gaussianity of the curvature perturbation would come from a contribution of the form $(\delta\sigma)^2$, where $\delta\sigma$ is gaussian. I analyse this situation allowing $\delta\sigma$ to be…

Astrophysics · Physics 2009-11-11 D. H. Lyth

We constrain two non-flat time-evolving dark energy cosmological models by using Hubble parameter data, Type Ia supernova apparent magnitude measurements, and baryonic acoustic oscillation peak length scale observations. The inclusion of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Omer Farooq , Data Mania , Bharat Ratra

The primordial curvature perturbation may be due to a `curvaton' field, which dominates (or almost dominates) the energy density before it decays. In the simplest version of the curvaton model the scale of inflation has to be quite high…

High Energy Physics - Phenomenology · Physics 2008-11-26 Konstantinos Dimopoulos , David H. Lyth , Yeinzon Rodriguez

The latest results from the Atacama Cosmology Telescope Collaboration have moved the preferred perturbation spectral index $n_{\rm s}$ closer towards one. We reanalyse constraints on the simplest version of the curvaton model, using $n_{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-20 Christian T. Byrnes , Marina Cortês , Andrew R. Liddle