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Related papers: Modulated inflation from kinetic term

200 papers

We present a complete numerical treatment of inflationary dynamics under the influence of stochastic corrections from sub-Hubble modes. We discuss how to exactly model the stochastic noise terms arising from the sub-Hubble quantum modes…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-02 Aritra De , Rafid Mahbub

There might be a light scalar field during inflation which is not responsible for the accelerating inflationary expansion. Then, its quantum fluctuation is stretched during inflation. This scalar field could be a curvaton, if it decays at a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Ki-Young Choi , Osamu Seto

The bispectrum of scalar mode density perturbations is analysed for the strong regime of warm inflationary models. This analysis generalises previous results by allowing damping terms in the inflaton equation of motion that are dependent on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Ian G Moss , Timothy Yeomans

In the modulated reheating scenario, the field that drives inflation has a spatially varying decay rate, and the resulting inhomogeneous reheating process generates adiabatic perturbations. We examine the statistical properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-28 Naoya Kobayashi , Takeshi Kobayashi , Adrienne L. Erickcek

We consider a class of multi-component hybrid inflation models whose evolution may be analytically solved under the slow-roll approximation. We call it multi-brid inflation (or $n$-brid inflation where $n$ stands for the number of inflaton…

Astrophysics · Physics 2009-10-09 Misao Sasaki

In this letter, we propose a single-field inflation model that realizes a slow-roll-to-ultra-slow-roll transition while keeping the second slow-roll parameter smoothly varying throughout. The model is built through a minimal modification by…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-19 Diego Cruces , Minxi He , Shi Pi , Jianing Wang , Masahide Yamaguchi , Yuhang Zhu

We investigate density perturbations generated through modulated reheating while inflation is driven by a conformally coupled scalar field. A large running of the spectral index is obtained, which reflects the basic nature of conformal…

High Energy Physics - Theory · Physics 2009-05-13 Takeshi Kobayashi , Shinji Mukohyama

String field theory motivated infinite-derivative models lead to non-local gravity modifications which form a promising class of quantum gravity candidates. In this paper we investigate effects of non-locality on the three-point function…

General Relativity and Quantum Cosmology · Physics 2025-08-07 Alexey S. Koshelev , Abhishek Naskar

We investigate the production process of induced gravity waves due to large scalar fluctuations in the paradigm of quintessential inflation. We numerically solve the Mukhanov-Sasaki equation for different sets of parameters to obtain the…

General Relativity and Quantum Cosmology · Physics 2023-11-09 Barnali Das , Nur Jaman , M Sami

The oscillating inflation model recently proposed by Damour and Mukhanov is investigated with a non-minimal coupling. Numerical study confirms an inflationary behavior and the density perturbation is obtained. A successful inflation…

High Energy Physics - Theory · Physics 2019-08-17 Jae-weon Lee , Seoktae Koh , Chanyong Park , Sang Jin Sin , Chul H. Lee

In this article we investigate the time evolution of the adiabatic(curvature) and isocurvature (entropy) spectral indices after end of inflation for all cosmological scales and two different initial conditions. For this purpose,we first…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Ali A. Asgari , Amir H. Abbassi

We propose a new mechanism to generate primordial curvature perturbations, based on the resonant production of particles during inflation. It is known that this phenomenon can trap the inflaton for a fraction of e-fold. This effect is…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 David Langlois , Lorenzo Sorbo

By assuming the field seeding the curvature perturbations $ \zeta $ is a dynamically arising condensate, we are able to derive the relation $ f_{NL} ^2 \simeq 10^8 H / M_c $ between the non-Gaussianity parameter $ f_{NL} $ and the ratio of…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-25 G. L. Alberghi , R. Casadio

We present a method by which cosmological perturbations can be quantitatively studied in single and multi-field inflationary models beyond linear perturbation theory. A non-linear generalization of the gauge-invariant Sasaki-Mukhanov…

Astrophysics · Physics 2009-11-10 G. I. Rigopoulos , E. P. S. Shellard

It has been argued that the standard inflationary scenario suffers from a serious deficiency as a model for the origin of the seeds of cosmic structure: it can not truly account for the transition from an early homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2013-03-25 Alberto Diez-Tejedor , Gabriel León , Daniel Sudarsky

We consider reheating after inflation with a non-standard kinetic term. We show that the difference in the kinetic term in different Hubble patches inherited from the long-wavelength moduli inhomogeneities may generate a significant level…

High Energy Physics - Phenomenology · Physics 2009-11-13 Tomohiro Matsuda

This paper considers warm inflation as an interesting application of multi-field inflation. Delta-N formalism is used for the calculation of the evolution of the curvature perturbations during warm inflation. Although the perturbations…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 Tomohiro Matsuda

There are many flat directions in SUSY models, which may dissipate their energy and source the radiation background during inflation. However, the only possibility that has been studied in this direction is warm inflation, which uses "warm"…

High Energy Physics - Phenomenology · Physics 2010-01-26 Tomohiro Matsuda

We propose a curvaton model in which the initial condition of the curvaton oscillation is determined by its attractor behavior during inflation. Assuming a chaotic inflation model, we find that the initial condition determined by the…

High Energy Physics - Phenomenology · Physics 2013-03-27 Keisuke Harigaya , Masahiro Ibe , Masahiro Kawasaki , Tsutomu T. Yanagida

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