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Related papers: Chaotic inflation and unitarity problem

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Chaotic inflation based on a simple monomial scalar potential, V(phi) ~ phi^p, is an attractive large-field model of inflation capable of generating a sizable tensor-to-scalar ratio r. Therefore, assuming that future CMB observations will…

High Energy Physics - Phenomenology · Physics 2014-12-24 Keisuke Harigaya , Masahiro Ibe , Kai Schmitz , Tsutomu T. Yanagida

We consider Supersymmetric (SUSY) and non-SUSY models of chaotic inflation based on the phi^n potential with 2<=n<=6. We show that the coexistence of a nonminimal coupling to gravity, fR=1+cR phi^(n/2), with a kinetic mixing of the form…

High Energy Physics - Phenomenology · Physics 2015-09-01 C. Pallis

Motivated by the result of Planck+BICEP/Keck recently released, we investigate the consistency of the multi-field inflation models in terms of the spectral index $n_s$ and the tensor-to-scalar ratio $r$. In this study, we focus on…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 Yukiyoshi Morishita , Tomo Takahashi , Shuichiro Yokoyama

N-flation is a radiatively stable scenario for chaotic inflation in which the displacements of $N \gg 1$ axions with decay constants $f_1 \le \ldots \le f_N < M_P$ lead to a super-Planckian effective displacement equal to the Pythagorean…

High Energy Physics - Theory · Physics 2016-07-13 Thomas C. Bachlechner , Mafalda Dias , Jonathan Frazer , Liam McAllister

The canonical multi-scalar field inflation where the kinetic and potential terms are sum-separable is ruled out by the current observations for the chaotic-type potential $V=\sum_{i} \mu_{i} \phi_{i}^{p}$. This paper explores the…

General Relativity and Quantum Cosmology · Physics 2025-04-29 Fereshteh Felegary , Seyed Ali Hosseini Mansoori , Tahere Fallahi Serish , Phongpichit Channuie

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

Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor…

High Energy Physics - Theory · Physics 2008-11-26 Lev Kofman , Shinji Mukohyama

A model of chaotic inflation based on the theory of a scalar field with potential \lambda\phi^4 perfectly matches the observational data if one adds to it a tiny non-minimal coupling to gravity -\xi/2 \phi^2 R with \xi > 0.002. We describe…

High Energy Physics - Theory · Physics 2015-06-16 Renata Kallosh , Andrei Linde

We determine the power spectrum for inflation models covering all regimes from cold (isentropic) to warm (nonisentropic) inflation. We work in the context of the stochastic inflation approach, which can nicely describe both types of…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-27 Rudnei O. Ramos , L. A. da Silva

We consider Supersymmetric (SUSY) and non-SUSY models of chaotic inflation based on the phi^n potential with n=2 or 4. We show that the coexistence of an exponential nonminimal coupling to gravity, fR=Exp(cR phi^p), with a kinetic mixing of…

High Energy Physics - Phenomenology · Physics 2017-10-25 C. Pallis

Warm inflation is extended from the canonical field to the noncanonical field with a general Lagrangian density having coupling form of kinetic and potential terms. We develop the motion equation of the noncanonical inflaton field, and…

General Relativity and Quantum Cosmology · Physics 2019-01-02 Kai Li , Xiao-Min Zhang , Hong-Yang Ma , Jian-Yang Zhu

We propose a class of inflation models in which the coefficient of the inflaton kinetic term rapidly changes with energy scale. This may occur especially if the inflaton moves over a long distance during inflation as in the case of…

High Energy Physics - Phenomenology · Physics 2014-11-21 Fuminobu Takahashi

If cosmological inflation is due to a slowly rolling single inflation field taking trans-Planckian values as suggested by the BICEP2 measurement of primordial tensor modes in CMB, embedding inflation into the Standard Model challenges…

High Energy Physics - Phenomenology · Physics 2014-10-14 Kristjan Kannike , Antonio Racioppi , Martti Raidal

Models of chaotic inflation with a fractional power-law potential are not only viable but also testable in the foreseeable future. We show that such models can be realized in simple strongly coupled supersymmetric gauge theories. In these…

High Energy Physics - Phenomenology · Physics 2015-06-12 Keisuke Harigaya , Masahiro Ibe , Kai Schmitz , Tsutomu T. Yanagida

Classic inflation, the theory described in textbooks, is based on the idea that, beginning from typical initial conditions and assuming a simple inflaton potential with a minimum of fine-tuning, inflation can create exponentially large…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-18 Anna Ijjas , Paul J. Steinhardt , Abraham Loeb

Transforming canonical scalars to the Einstein frame can give a multi-field generalization of pole inflation (namely, a scalar with a divergent kinetic term) at vanishing field-dependent Planck mass. However, to obtain an attractor, the…

High Energy Physics - Theory · Physics 2022-09-07 Sotirios Karamitsos , Alessandro Strumia

An appealing explanation for the Planck data is provided by inflationary models with a singular non-canonical kinetic term: a Laurent expansion of the kinetic function translates into a potential with a nearly shift-symmetric plateau in…

High Energy Physics - Theory · Physics 2016-01-08 Benedict J. Broy , Mario Galante , Diederik Roest , Alexander Westphal

We extend the idea of assisted inflation to the case of power-law potentials and demonstrate the simultaneous resolution of two major problems that plague chaotic inflation. The implementation of the same idea in the framework of a…

High Energy Physics - Phenomenology · Physics 2007-05-23 Panagiota Kanti

We present a two-field inflation model where inflaton field has a non-canonical kinetic term due to the presence of a dilaton field. It is a two-parameter generalization of one-parameter Brans-Dicke gravity in the Einstein frame. We show…

High Energy Physics - Phenomenology · Physics 2016-08-03 Girish Kumar Chakravarty , Suratna Das , Gaetano Lambiase , Subhendra Mohanty

We investigate chaotic inflation models with two scalar fields, such that one field (the inflaton) rolls while the other is trapped in a false vacuum state. The false vacuum becomes unstable when the inflaton field falls below some critical…

Astrophysics · Physics 2009-10-22 Edmund J Copeland , Andrew R Liddle , David H Lyth , Ewan D Stewart , David Wands