English
Related papers

Related papers: Constant roll inflation in multifield models

200 papers

We adopt the double field natural inflation model motivated by the non-perturbative effects of supergravity and superstring theory to do the slow roll analysis. We show that when the parameters are suitably chosen, there exist ranges of…

General Relativity and Quantum Cosmology · Physics 2019-04-12 Ping Kwan Man Ellgan

In this work we shall investigate the phenomenological implications of the constant-roll condition on a $k$-Inflation theory of gravity. The latter theories are particularly promising, since these remained robust to the results of GW170817,…

General Relativity and Quantum Cosmology · Physics 2020-01-29 S. D. Odintsov , V. K. Oikonomou

In this work, we investigate how a smooth transition from a constant-roll to a slow-roll inflationary era may be realized, in the context of a canonical scalar field theory. We study in some detail the dynamical evolution of the…

General Relativity and Quantum Cosmology · Physics 2018-02-14 V. K. Oikonomou

We explore the inflationary phase of a scalar field with a kinetic term non-minimally coupled to gravity. We find that one of the slow-roll conditions is naturally consequence of the equation of motion of the scalar field. Thus, slow-roll…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-16 Amir Ghalee

In this work, we explore the prospect of generalizing the constant-roll condition in canonical inflationary model to non-canonical models. To find a natural generalization, we focus on three manifestations of this condition and construct…

General Relativity and Quantum Cosmology · Physics 2024-05-07 S. Mohammad Ahmadi , Nahid Ahmadi , Mehdi Shokri

Dirac-Born-Infeld scalar field theories which appear in the context of inflation in string theory in general have a field dependent speed of sound. It is however possible to write down DBI models which possess exact solutions characterized…

Astrophysics · Physics 2009-06-23 Michal Spalinski

We discuss the usefulness and theoretical consistency of different entropy variables used in the literature to describe isocurvature perturbations in multifield inflationary models with a generic curved field space. We clarify which is the…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-09 Michele Cicoli , Veronica Guidetti , Francesco Muia , Francisco G. Pedro , Gian Paolo Vacca

We study a single field inflationary model modified by a non-minimal coupling term between the Ricci scalar $R$ and the scalar field $\varphi$ in the context of constant-roll inflation. The first-order formalism is used to analyse the…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Mehdi Shokri , Jafar Sadeghi , Mohammad Reza Setare , Salvatore Capozziello

We develop a general formalism for analyzing linear perturbations in multiple-field cosmological inflation based on the gauge-ready approach. Our inflationary model consists of an arbitrary number of scalar fields with non-minimal kinetic…

Astrophysics · Physics 2009-11-13 Joydev Lahiri , Gautam Bhattacharya

In this work, I consider an inflation model with a quadratic potential and a negative cosmological constant. An analytical solution of the equation of motion for the inflaton field is found without slow-roll approximation. The result is…

High Energy Physics - Phenomenology · Physics 2023-04-19 Chia-Min Lin

Usually inflation ends either by a slow rolling of the inflaton field, which gradually becomes faster and faster, or by a first-order phase transition. We describe a model where inflation ends in a different way, due to a very rapid rolling…

Astrophysics · Physics 2009-09-29 Andrei Linde

We review the theory of inflation with single and multiple fields paying particular attention to the dynamics of adiabatic and entropy/isocurvature perturbations which provide the primary means of testing inflationary models. We review the…

Astrophysics · Physics 2008-11-26 Bruce A. Bassett , Shinji Tsujikawa , David Wands

We investigate multi-field inflationary scenarios with fields that drop out of the model in a staggered fashion. This feature is natural in certain multi-field inflationary setups within string theory; for instance, it can manifest itself…

High Energy Physics - Theory · Physics 2009-12-10 Diana Battefeld , Thorsten Battefeld , Anne-Christine Davis

We generalize the consistency condition for the three-point function in single field inflation to the case of dissipative, multi-field, single-clock models. We use the recently introduced extension of the effective field theory of inflation…

High Energy Physics - Theory · Physics 2015-06-05 Diana Lopez Nacir , Rafael A. Porto , Matias Zaldarriaga

We investigate in detail the attractor behavior of some inflationary models based on braneworld dynamics under the constant-roll condition. We describe the dynamics of the models, assuming that the second slow-roll parameter remains…

General Relativity and Quantum Cosmology · Physics 2025-04-29 Goran S. Djordjevic , Neven Bilić , Dragoljub D. Dimitrijevic , Milan Milosevic , Marko Stojanovic

The framework of a kind of noncanonical warm inflation is introduced, and the dynamical equations of this scenario are presented. We propose the slow roll approximations and give some redefining slow roll parameters in this scenario which…

General Relativity and Quantum Cosmology · Physics 2021-01-13 Xiao-Min Zhang , Ang Fu , Kai Li , Qian Li , Peng-Cheng Chu , Hong-Yang Ma , Jian-Yang Zhu

The dynamics of hybrid models is usually approximated by the evolution of a scalar field slowly rolling along a nearly flat valley. Inflation ends with a waterfall phase, due to a tachyonic instability. This final phase is usually assumed…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-27 Sébastien Clesse

We explore inflationary cosmology in a theory where there are two scalar fields which non-minimally couple to the Ricci scalar and an additional $R^2$ term, which breaks the conformal invariance. Particularly, we investigate the slow-roll…

High Energy Physics - Theory · Physics 2015-07-10 Kazuharu Bamba , Sergei D. Odintsov , Petr V. Tretyakov

In this paper we discuss a multi-field model of inflation in which generally all fields are non-minimally coupled to the Ricci scalar and have non-canonical kinetic terms. The background evolution and first-order perturbations for the model…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Jonathan White , Masato Minamitsuji , Misao Sasaki

Multifield models of inflation with nonminimal couplings are in excellent agreement with the recent results from {\it Planck}. Across a broad range of couplings and initial conditions, such models evolve along an effectively single-field…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-08 David I. Kaiser , Evangelos I. Sfakianakis