English
Related papers

Related papers: Non-Gaussianity in multi-field inflation

200 papers

Quantization implies independent degrees of freedom that do not appear in the classical theory, given by fluctuations, correlations, and higher moments of a state. A systematic derivation of the resulting dynamical systems is presented here…

High Energy Physics - Theory · Physics 2021-08-24 Martin Bojowald , Suddhasattwa Brahma , Sean Crowe , Ding Ding , Joseph McCracken

We consider a simple inflation model with a complex scalar field coupled to gravity non-minimally. Both the modulus and the angular directions of the complex scalar are slowly rolling, leading to two-field inflation. The modulus direction…

High Energy Physics - Phenomenology · Physics 2015-05-28 Jinn-Ouk Gong , Hyun Min Lee

In this paper, we investigate the primordial perturbations of inflation model induced from the multi-field mimetic gravity, where there are two field during inflation, and thus both adiabatic and isocurvature perturbation modes are…

High Energy Physics - Theory · Physics 2023-02-22 Xin-zhe Zhang , Lei-hua Liu , Taotao Qiu

The general kind noncanonical warm inflation is introduced and its total non-Gaussianity of perturbation on uniform energy density hypersurfaces is studied. The total non-Gaussianity contains two complementary parts: the three- and the…

General Relativity and Quantum Cosmology · Physics 2019-12-19 Xiao-Min Zhang , Kai Li , Hong-Yang Ma , Qian Liu , Jian-Yang Zhu

We present a review of vector field models of inflation and, in particular, of the statistical anisotropy and non-Gaussianity predictions of models with SU(2) vector multiplets. Non-Abelian gauge groups introduce a richer amount of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Emanuela Dimastrogiovanni , Nicola Bartolo , Sabino Matarrese , Antonio Riotto

We consider inflation in the system containing a Ricci scalar squared term and a canonical scalar field with quadratic mass term. In the Einstein frame this model takes the form of a two-field inflation model with a curved field space, and…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-01 Taro Mori , Kazunori Kohri , Jonathan White

In any realistic particle physics model of inflation, the inflaton can be expected to couple to other fields. We consider a model with a dilaton-like coupling between a U(1) gauge field and a scalar inflaton. We show that this coupling can…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Neil Barnaby , Ryo Namba , Marco Peloso

Multiple fields can become dynamical during the inflationary epoch. We consider an example where a light field acquires isocurvature fluctuations during inflation and contributes to the dark matter abundance at late times. Interactions…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-08 Michael Geller , Soubhik Kumar , Lian-Tao Wang

We explore the super-horizon evolution of the two-point and three-point correlation functions of the primordial density perturbation in randomly-generated multi-field potentials. We use the Transport method to evolve perturbations and give…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Jonathan Frazer , Andrew R Liddle

Primordial non-Gaussianity generated in an inflationary model where inflation is preceded by a radiation era is discussed. It is shown that both bispectrum and trispectrum non-Gaussianities are enhanced due to the presence of…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-04 Suratna Das

We study the non-Gaussian tail of the curvature fluctuation, $\zeta$, in an inflationary scenario with a transient ultra slow-roll phase that generates a localized large enhancement of the spectrum of $\zeta$. To do so, we implement a…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-08 Guillermo Ballesteros , Jesús Gambín Egea , Thomas Konstandin , Alejandro Pérez Rodríguez , Mathias Pierre , Julián Rey

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 study non-Gaussianity of density perturbations generated by an axionic curvaton, focusing on the case that the curvaton sits near the hilltop of the potential during inflation. Such hilltop curvatons can generate a red-tilted density…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-15 Masahiro Kawasaki , Takeshi Kobayashi , Fuminobu Takahashi

Extending the analysis of [1011.4934] beyond the bispectrum, we explore the superhorizon generation of local non-gaussianities and their subsequent approach to adiabaticity. Working with a class of two field models of inflation with…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-06 Joel Meyers , Navin Sivanandam

The non-Gaussianity of inflationary perturbations, as encoded in the bispectrum (or 3-point correlator), has become an important additional way of distinguishing between inflation models, going beyond the linear Gaussian perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-23 Bartjan van Tent

We perform a general study of primordial scalar non-Gaussianities in single field inflationary models in Einstein gravity. We consider models where the inflaton Lagrangian is an arbitrary function of the scalar field and its first…

High Energy Physics - Theory · Physics 2009-11-11 Xingang Chen , Min-xin Huang , Shamit Kachru , Gary Shiu

We study the structure of multi-field inflation models where the primordial curvature perturbation is able to vigorously interact with an ultra-light isocurvature field -- a massless fluctuation orthogonal to the background inflationary…

High Energy Physics - Theory · Physics 2020-10-14 Ana Achúcarro , Gonzalo Palma , Dong-Gang Wang , Yvette Welling

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

Tensor non-Gaussianity represents an important future probe of the physics of inflation. Inspired by recent works, we elaborate further on the possibility of significant primordial tensor non-Gaussianities sourced by extra fields during…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-20 Emanuela Dimastrogiovanni , Matteo Fasiello , Gianmassimo Tasinato , David Wands

In a variety of models the motion of the inflaton may trigger the production of some non-inflaton particles during inflation, for example via parametric resonance or a phase transition. Such models have attracted interest recently for a…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 Neil Barnaby