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Related papers: The shape of non-Gaussianities

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We perform cosmological N-body simulations with non-Gaussian initial conditions generated from two independent fields. The dominant contribution to the perturbations comes from a purely Gaussian field, but we allow the second field to have…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-25 Saroj Adhikari , Sarah Shandera , Neal Dalal

We update predictions for observables in the "delicate" D3/anti-D3 inflationary model on the conifold. We use a full CMB likelihood calculation to assess goodness-of-fit, which is necessary because in this model the zeta power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-11 Kareem Marzouk , Alessandro Maraio , David Seery

Primordial non-Gaussianity is generated by interactions of the inflaton field, either self-interactions or couplings to other sectors. These two physically different mechanisms can lead to nearly indistinguishable bispectra of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Neil Barnaby , Sarah Shandera

We develop a formalism to study non-Gaussianity in both curvature and isocurvature perturbations. It is shown that non-Gaussianity in the isocurvature perturbation between dark matter and photons leaves distinct signatures in the CMB…

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

Inflation can be supported in very steep potentials if it is generated by rapidly turning fields, which can be natural in negatively curved field spaces. The curvature perturbation, $\zeta$, of these models undergoes an exponential,…

High Energy Physics - Theory · Physics 2019-12-18 Theodor Bjorkmo , Ricardo Z. Ferreira , M. C. David Marsh

We explore the superhorizon generation of large fnl of the local form in two field inflation. We calculate the two- and three-point observables in a general class of potentials which allow for an analytic treatment using the delta N…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-17 Joel Meyers , Navin Sivanandam

In this work we study the properties of the mass density field in the non-Gaussian world models simulated by Grossi et al. 2007. In particular we focus on the one-point density probability distribution function of the mass density field in…

Astrophysics · Physics 2010-03-26 M. Grossi , E. Branchini , K. Dolag , S. Matarrese , L. Moscardini

We study the bispectrum of the curvature perturbation on uniform energy density hypersurfaces in models of inflation with two scalar fields evolving simultaneously. In the case of a separable potential, it is possible to compute the…

Astrophysics · Physics 2009-11-11 Filippo Vernizzi , David Wands

The phases of the Fourier transform of any linear cosmological perturbation may be random (the Gaussian case) or not (the non-Gaussian case). If a non-Gaussian inhomogeneity was generated during the inflationary era by some process of very…

Astrophysics · Physics 2007-05-23 Carlo Baccigalupi

We discuss some entanglement features associated with cubic non-Gaussian perturbations in single-field inflationary scenarios. We adopt standard momentum-space techniques to show how multipartite entanglement arises for inflationary…

General Relativity and Quantum Cosmology · Physics 2025-12-01 Alessio Belfiglio , Roberto Franzosi , Orlando Luongo

We describe a two-field model that generalizes Natural Inflation, in which the inflaton is the pseudo-Goldstone boson of an approximate symmetry that is spontaneously broken, and the radial mode is dynamical. We analyze how the dynamics…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 Simon Riquelme

We compute a novel type of large non-Gaussianity due to small periodic features in general single field inflationary models. We show that the non-Bunch-Davies vacuum component generated by features, although has a very small amplitude, can…

High Energy Physics - Theory · Physics 2010-12-09 Xingang Chen

Inflationary models predict a definite, model independent, angular dependence for the three-point correlation function of $\Delta T/T$ at large angles (greater than $\sim 1^\circ$) which we calculate. The overall amplitude is model…

Astrophysics · Physics 2009-10-22 Toby Falk , Raghavan Rangarajan , Mark Srednicki

We calculate the perturbed action, at second and third order, for a massive three-form field minimally coupled to gravity, and use it to explore the observational predictions of three-form inflation. One intriguing result is that the value…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-11 David J. Mulryne , Johannes Noller , Nelson J. Nunes

In the context of Type IIB LARGE volume orientifold setup equipped with poly-instanton corrections, the standard single-field poly-instanton inflation driven by a 'Wilson' divisor volume modulus is generalized by the inclusion of respective…

High Energy Physics - Theory · Physics 2013-03-28 Xin Gao , Pramod Shukla

We study the non-Gaussianity in the simplest infrared (IR) model of the DBI inflation. We show that the non-Gaussianity in such a model is compatible with the current observational bound, and is within the sensitivity of future experiments.…

Astrophysics · Physics 2009-11-13 Xingang Chen

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

Focusing on the local type primordial non-Gaussianities, we study the bispectrum and trispectrum during a non-minimal slow-roll inflation. We use the so-called $\delta N$ formalism to investigate the super-horizon evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-28 Kosar Asadi , Kourosh Nozari

Many models of inflation predict oscillatory features in the bispectrum of primordial fluctuations. Since it has been shown that primordial non-Gaussianity can lead to a scale-dependent halo bias, we investigate the effect of oscillations…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-20 Francis-Yan Cyr-Racine , Fabian Schmidt