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Related papers: Non-Gaussianity in three fluid curvaton model

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We consider general mixtures of isocurvature and adiabatic cosmological perturbations. With a minimal assumption set consisting of the linearized Einstein equations and a primordial perfect fluid we derive the second-order action and its…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-20 J. Noller , J. Magueijo

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

We calculate the scale dependence of the bispectrum and trispectrum in (quasi) local models of non-Gaussian primordial density perturbations, and characterize this scale dependence in terms of new observable parameters. They can help to…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-12 Christian T. Byrnes , Mischa Gerstenlauer , Sami Nurmi , Gianmassimo Tasinato , David Wands

We use the \delta N formalism to study the trispectrum T_\zeta of the primordial curvature perturbation \zeta when the latter is generated by vector field perturbations, considering the tree-level and one-loop contributions. The order of…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-12 Cesar A. Valenzuela-Toledo , Yeinzon Rodriguez

The transverse momentum per particle, $[p_t]$, fluctuates event by event in ultrarelativistic nucleus-nucleus collisions, for a given multiplicity. These fluctuations are small and approximately Gaussian, but a non-zero skewness has been…

Nuclear Theory · Physics 2023-08-21 Rupam Samanta , João Paulo Picchetti , Matthew Luzum , Jean-Yves Ollitrault

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

The goal of the present paper is to set initial conditions for structure formation at non-linear order, consistent with general relativity, while also allowing for primordial non-Gaussianity. We use the non-linear continuity and Raychauduri…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Marco Bruni , Juan Carlos Hidalgo , Nikolai Meures , David Wands

I adopt a formalism previously developed by Catelan and Theuns (CT) in order to estimate the impact of primordial non-Gaussianity on the quasi-linear spin growth of cold dark matter protostructures. A variety of bispectrum shapes are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 C. Fedeli

Using the \delta N formalism we consider the non-linear curvature perturbation in multi-field models of inflation with non-minimal coupling. In particular, we focus on the relation between the \delta N formalism as applied in the…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-25 Jonathan White , Masato Minamitsuji , Misao Sasaki

We demonstrate novel features in the behavior of the second and third order non-linearity parameters of the curvature perturbation, namely, $f_{NL}$ and $g_{NL}$, arising from non-linear motion of curvaton field. We investigate two classes…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-28 Pravabati Chingangbam , Qing-Guo Huang

Enormous information about interactions is contained in the non-Gaussianities of the primordial curvature perturbations, which are essential to break the degeneracy of inflationary models. We study the primordial bispectra for G-inflation…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Fengge Zhang , Yungui Gong , Jiong Lin , Yizhou Lu , Zhu Yi

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

Recent progress in experimental techniques such as single particle tracking allows to analyze both nonequilibrium properties and approach to equilibrium. There are examples showing that processes occurring at finite timescales are…

Statistical Mechanics · Physics 2025-01-24 I. G. Marchenko , I. I. Marchenko , J. Łuczka , J. Spiechowicz

We compute the amplitude of the non-Gaussianities in inflationary models with multiple, uncoupled scalar fields. This calculation thus applies to all models of assisted inflation, including N-flation, where inflation is driven by multiple…

Astrophysics · Physics 2010-10-27 Thorsten Battefeld , Richard Easther

We have studied modulated inflation that generates curvature perturbation from light-field fluctuation. As discussed in previous works, even if the fluctuation of the inflaton itself does not generate the curvature perturbation at the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Tomohiro Matsuda

We derive a Thermodynamic Uncertainty Relation bounding the mean squared displacement of a Gaussian process with memory, driven out of equilibrium by unbalanced thermal baths and/or by external forces. Our bound is tighter with respect to…

Statistical Mechanics · Physics 2023-05-23 Andrea Plati , Andrea Puglisi , Alessandro Sarracino

Non-reciprocal systems can be thought of as disobeying Newtons third law - an action does not cause an equal and opposite reaction. In recent years there has been a dramatic rise in interest towards such systems. On a fundamental level,…

Statistical Mechanics · Physics 2024-12-06 Sergei Shmakov , Glasha Osipycheva , Peter B. Littlewood

We study perturbations in the multi-field axion Nflation model, taking account of the full cosine potential. We find significant differences with previous analyses which made a quadratic approximation to the potential. The tensor-to-scalar…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Soo A Kim , Andrew R Liddle , David Seery

Non-Gaussianity of the primordial density perturbations provides an important measure to constrain models of inflation. At cubic order the non-Gaussianity is captured by two parameters $\tau_{\rm NL}$ and $g_{\rm NL}$ that determine the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-12 Chang Feng , Asantha Cooray , Joseph Smidt , Jon O'Bryan , Brian Keating , Donough Regan

It was pointed out recently that in some inflationary models quantum loops containing a scalar of mass $m$ that couples to the inflaton can be the dominant source of primordial non-Gaussianities. We explore this phenomenon in the simplest…

High Energy Physics - Phenomenology · Physics 2019-03-27 Haipeng An , Mark B. Wise , Zipei Zhang