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Related papers: Multi-Stream Inflation

200 papers

The statistics of multi-field inflation are investigated using the stochastic approach. We analytically obtain the probability distribution function of fields with the scaling approximation by extending the previous work by Amendola. The…

Astrophysics · Physics 2009-11-11 Takeshi Hattori , Kazuhiro Yamamoto

While detection of the "local form" bispectrum of primordial perturbations would rule out all single-field inflation models, multi-field models would still be allowed. We show that multi-field models described by the $\delta N$ formalism…

General Relativity and Quantum Cosmology · Physics 2011-07-28 Naonori S. Sugiyama , Eiichiro Komatsu , Toshifumi Futamase

We study the scalar-tensor-tensor non-Gaussian signal in an inflationary model comprising also an axion coupled with SU(2) gauge fields. In this set-up, metric fluctuations are sourced by the gauge fields already at the linear level…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-28 Emanuela Dimastrogiovanni , Matteo Fasiello , Robert J. Hardwick , Hooshyar Assadullahi , Kazuya Koyama , David Wands

Based on the flux-scaling scenario we study a model consisting on Type IIB string theory compactified on a Calabi-Yau manifold with a frozen complex structure in the presence of generic fluxes. The model contains (meta)stable Minkowski and…

High Energy Physics - Theory · Physics 2021-07-28 Cesar Damian , Oscar Loaiza-Brito

Perturbations in cosmic microwave background (CMB) photons and large scale structure of the universe are sourced primarily by the curvature perturbation which is widely believed to be produced during inflation. In this paper we present a…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Pavel Friedrich , Tomislav Prokopec

The leading candidate for the very early universe is described by a period of rapid expansion known as inflation. While the standard paradigm invokes a single slow-rolling field, many different models may be constructed which fit the…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-30 D. M. Regan

The first year results of WMAP tentatively indicate running of the spectral index as well as a deficit of power in the low multipoles in the CMB spectrum. The former can be rather easily understood in the noncommutative inflation model, and…

Astrophysics · Physics 2009-11-10 Qing-Guo Huang , Miao Li

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

Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-10 David I. Kaiser

We present a simple way to calculate non-Gaussianity in inflation using fully non-linear equations on long wavelengths with stochastic sources to take into account the short-wavelength quantum fluctuations. Our formalism includes both…

Astrophysics · Physics 2009-11-10 G. I. Rigopoulos , E. P. S. Shellard , B. J. W. van Tent

We analyze the signatures of inflationary models that are coupled to strongly interacting field theories, a basic class of multifield models also motivated by their role in providing dynamically small scales. Near the squeezed limit of the…

High Energy Physics - Theory · Physics 2015-06-12 Daniel Green , Matthew Lewandowski , Leonardo Senatore , Eva Silverstein , Matias Zaldarriaga

The methods of effective field theory are used to study generic theories of inflation with a single inflaton field and to perform a general analysis of the associated non-Gaussianities. We investigate the amplitudes and shapes of the…

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

Inflationary scenarios motivated by the Minimal Supersymmetric Standard Model (MSSM) where five scalar fields are non-minimally coupled to gravity are considered. The potential of the model and the function of non-minimal coupling are…

High Energy Physics - Phenomenology · Physics 2018-06-01 M. N. Dubinin , E. Yu. Petrova , E. O. Pozdeeva , S. Yu. Vernov

We reconsider the observed CMB dipolar asymmetry in the context of open inflation, where a supercurvature mode might survive the bubble nucleation. If such a supercurvature mode modulates the amplitude of the curvature power spectrum, it…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Christian Byrnes , Guillem Domènech , Misao Sasaki , Tomo Takahashi

We use holographic techniques to compute inflationary non-Gaussianities for general single-field inflation, including models with a non-trivial sound speed. In this holographic approach, the inflationary dynamics is captured by a relevant…

High Energy Physics - Theory · Physics 2016-12-14 Hiroshi Isono , Toshifumi Noumi , Gary Shiu , Sam S. C. Wong , Siyi Zhou

We consider a model of inflation in which the inflaton field is a rolling axion with a potential which is flat enough to support an intermediate phase of USR inflation. Because of the Chern-Simons interaction, one polarization of the gauge…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-04 Alireza Talebian , Hassan Firouzjahi

In this note, we will introduce an action for warm inflation model with direct coupling between the pseudoscalar field and mass-less $SU(2)$ gauge fields. The potential of inflaton is protected against the thermal corrections in a thermal…

General Relativity and Quantum Cosmology · Physics 2019-08-21 Vahid. Kamali

We revisit an extension of the well-known formalism for gauge-invariant scalar metric fluctuations, to study the spectrums for both, the inflaton and gauge invariant (scalar) metric fluctuations in the framework of a single field…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Mariano Anabitarte , Mauricio Bellini

We explore a model of two-field inflation with nonminimal kinetic terms in which two identical matter sectors decoupled from each other may reheat to different temperatures while preserving the symmetry of the Lagrangian. This scenario is…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 James M. Cline , Jean-Samuel Roux

In this paper, we present a non-Gaussianity consistency relation that enables the calculation of the squeezed limit bispectrum of the curvature perturbation in single-field inflationary models by carefully inspecting the background…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 Mohammad Hossein Namjoo