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Related papers: Two-field constant roll inflation

200 papers

We consider models of a scalar field coupled to quadratic $R\!+\!R^2$ gravity in the framework of the Palatini formulation. The resulting Einstein-frame generalized $k$-inflation effective theory is analyzed assuming that the constant-roll…

General Relativity and Quantum Cosmology · Physics 2020-04-29 Ignatios Antoniadis , Angelos Lykkas , Kyriakos Tamvakis

We prove the existence of a general class of rapidly turning two-field inflationary attractors. By only requiring a large, slowly varying turn rate, we solve the system completely without specifying any metric or potential, and prove the…

High Energy Physics - Theory · Physics 2019-07-03 Theodor Bjorkmo

The calculation of scalar gravitational and matter perturbations during multiple-field inflation valid to first order in slow roll is discussed. These fields may be the coordinates of a non-trivial field manifold and hence have non-minimal…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. J. W. van Tent , S. Groot Nibbelink

We study the dual 3d Euclidean RG flow of single-field slow-roll Inflation using the postulates of the dS/CFT correspondence. For that purpose we solve for the inflationary fluctuation at all times using a matching procedure between two…

High Energy Physics - Theory · Physics 2015-06-17 Uri Kol

The previously introduced class of two-parametric phenomenological inflationary models in General Relativity in which the slow-roll assumption is replaced by the more general, constant-roll condition is generalized to the case of $f(R)$…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-15 Hayato Motohashi , Alexei A. Starobinsky

A systematic analysis of possibilities for realizing single-field F-term axion monodromy inflation via the flux-induced superpotential in type IIB string theory is performed. In this well-defined setting the conditions arising from moduli…

High Energy Physics - Theory · Physics 2015-01-14 Ralph Blumenhagen , Daniela Herschmann , Erik Plauschinn

We show that inflation in type IIB string theory driven by the volume modulus can be realized in the context of the racetrack-based Kallosh-Linde model (KL) of moduli stabilization. Inflation here arises through the volume modulus…

High Energy Physics - Theory · Physics 2009-09-29 Andrei Linde , Alexander Westphal

We analyze the flow into inflation for generic "single-clock" systems, by combining an effective field theory approach with a dynamical-systems analysis. In this approach, we construct an expansion for the potential-like term in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-15 Feraz Azhar , David I. Kaiser

We investigate the possibility that spiral inflation can be realized using the near-conifold flux potentials for the complex structure moduli in type IIB string theory compactified on a Calabi-Yau manifold. Using the explicit form of the…

High Energy Physics - Theory · Physics 2013-08-05 Pontus Ahlqvist , Brian Greene , David Kagan

We study the possibility of extended inflation in the effective theory of gravity from strings compactified to four dimensions and find that it strongly depends on the mechanism of supersymmetry breaking. We consider a general class of…

High Energy Physics - Theory · Physics 2009-10-22 J. Garcia-Bellido , M. quiros

We construct a multi-field inflationary model consisting of multiple K\"ahler moduli derived from type IIB string compactification in the large volume limit. The model consists of both heavy and light fields, with the former being frozen…

High Energy Physics - Theory · Physics 2009-12-09 Per Berglund , Guoqin Ren

We present two cases where the addition of the $R^2$ term to an inflationary model leads to single-field inflation instead of two-field inflation as is usually the case. In both cases we find that the effect of the $R^2$ term is to reduce…

General Relativity and Quantum Cosmology · Physics 2020-01-01 Ignatios Antoniadis , Alexandros Karam , Angelos Lykkas , Thomas Pappas , Kyriakos Tamvakis

In this work, we study a constant-roll inflationary model in the Palatini formalism using modified gravity. Here our action consists a non-minimal coupling of a scalar field $\phi$ with Ricci scalar $R$ in a general form of $f(R,\phi)$.…

General Relativity and Quantum Cosmology · Physics 2023-04-19 Sukanta Panda , Arun Rana , Rahul Thakur

An attractive candidate for the inflaton is an axion slowly rolling down a flat potential protected by a perturbative shift symmetry. Realisations of this idea within large field, natural and monomial inflation have been disfavoured by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Susha Parameswaran , Gianmassimo Tasinato , Ivonne Zavala

We derive a closed-form, analytical expression for the spectrum of long-wavelength density perturbations in inflationary models with two (or more) inflaton degrees of freedom that is valid in the slow-roll approximation. We illustrate…

Astrophysics · Physics 2009-09-15 V. F. Mukhanov , Paul J. Steinhardt

We consider a model of two-field inflation, containing an ordinary scalar field and a DBI field. We work beyond the slow-roll approximation, but we assume a separable Hubble parameter. We then derive the form of potential in this framework…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Kourosh Nozari , Kosar Asadi

In this paper, we explore the inflationary dynamics of the $\beta$-exponential potential model, where a scalar field couples to quadratic $(R + R^2)$ gravity. In this model, the inflaton is the field that determines the size of the extra…

General Relativity and Quantum Cosmology · Physics 2026-01-15 Ozan Sargın

In this work we generalize the constant-roll condition for minimally coupled canonical scalar field inflation. Particularly, we shall assume that the scalar field satisfies the condition $\ddot{\phi}=\alpha (\phi) V'(\phi)$, and we derive…

General Relativity and Quantum Cosmology · Physics 2022-05-25 V. K. Oikonomou

Constant-roll inflation is a distinctive class of phenomenological inflationary models in which the inflaton's rate of roll remains constant. It provides an exact solution that is compatible with the latest observational constraints and…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-25 Hayato Motohashi

In this talk we describe recent progress in construction of inflationary models in the context of string theory with flux compactification and moduli stabilization. We also discuss a possibility to test string theory by cosmological…

High Energy Physics - Theory · Physics 2010-04-06 Renata Kallosh