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Related papers: Inflationary $\alpha$-attractor cosmology: A globa…

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The equations for quintessential $\alpha$-attractor inflation with a single scalar field, radiation and matter in a spatially flat FLRW spacetime are recast into a regular dynamical system on a compact state space. This enables a complete…

General Relativity and Quantum Cosmology · Physics 2024-02-08 Artur Alho , Claes Uggla

We consider the familiar problem of a minimally coupled scalar field with quadratic potential in flat Friedmann-Lema\^itre-Robertson-Walker cosmology to illustrate a number of techniques and tools, which can be applied to a wide range of…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Artur Alho , Claes Uggla

We consider a generic class of the so-called inflationary $-\alpha$ attractor models and compute the cosmological observables in the Einstein and Jordan frames, of the corresponding $F(R)-$gravity theory. We find that the two sets coincide…

High Energy Physics - Theory · Physics 2017-09-06 A. Kuiroukidis

We explore in detail the dynamics of multi-field inflationary models. We first revisit the two-field case and rederive the coordinate independent expression for the attractor solution with either small or large turn rate, emphasizing the…

High Energy Physics - Theory · Physics 2023-11-13 Perseas Christodoulidis , Robert Rosati

In this paper, we consider spatially flat FLRW cosmological models in two contexts in an attempt to derive a set of conditions that characterize when such models exhibit oscillatory behaviour. In the first case, we consider a spatially flat…

General Relativity and Quantum Cosmology · Physics 2017-06-12 Ikjyot Singh Kohli

During the inflationary epoch,geometry of the universe may be described by quasi-de Sitter space. On the other hand,maximally extended de Sitter metric in the comoving coordinates accords with a special FLRW model with positive spatial…

General Relativity and Quantum Cosmology · Physics 2016-01-20 A. A. Asgari , A. H. Abbassi

We consider a minimally coupled scalar field with a monomial potential and a perfect fluid in flat FLRW cosmology. We apply local and global dynamical systems techniques to a new three-dimensional dynamical systems reformulation of the…

General Relativity and Quantum Cosmology · Physics 2015-08-05 Artur Alho , Juliette Hell , Claes Uggla

We explore the inflationary evolution and observational viability of the $\alpha$-attractor E-model in the framework of warm inflation, focusing on both weak and strong dissipative regimes, with a dissipation coefficient linear in…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-10 Bhargabi Saha , Malay K. Nandy

We investigate the dynamics of the recently proposed model of assisted inflation. In this model an arbitrary number of scalar fields with exponential potentials evolve towards an inflationary scaling solution, even if each of the individual…

Astrophysics · Physics 2016-08-25 Karim A. Malik , David Wands

The slow-roll approximation to inflation is ultimately justified by the presence of inflationary attractors for the orbits of the solutions of the dynamical equations in phase space. There are many indications that the inflaton field…

General Relativity and Quantum Cosmology · Physics 2011-08-11 Valerio Faraoni

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 study an inflation mechanism based on attractor properties in cosmological evolutions of a spatially flat Friedmann-Robertson-Walker spacetime based on the Einstein-scalar field theory. We find a new way to get the Hamilton-Jacobi…

General Relativity and Quantum Cosmology · Physics 2013-12-10 Hyeong-Chan Kim

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

Over the last few years, a large family of cosmological attractor models has been discovered, which can successfully match the latest inflation-related observational data. Many of these models can also describe a small cosmological constant…

High Energy Physics - Theory · Physics 2018-07-02 Yashar Akrami , Renata Kallosh , Andrei Linde , Valeri Vardanyan

We investigate the observational viability of a class of $\alpha$-attractors inflationary models in light of the most recent Cosmic Microwave Background (CMB) and Large-Scale Structure (LSS) data. By considering a double-well potential we…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-04 J. G. Rodrigues , S. Santos da Costa , J. S. Alcaniz

We reconsider the dynamical systems approach to analyze inflationary universe in the Jordan frame models of scalar field nonminimally coupled to curvature. The adopted set of variables allows us to clearly distinguish between different…

General Relativity and Quantum Cosmology · Physics 2022-03-03 Laur Järv , Alexey Toporensky

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

In the framework of a flat FLRW model we derive an inflationary regime in which the scalar field, laying on the plateau of its potential, admits a linear time dependence and remains close to a constant value. The behaviour of inhomogeneous…

General Relativity and Quantum Cosmology · Physics 2016-11-09 Giovanni Imponente , Giovanni Montani

In the framework of a flat Friedmann-Lema{\^\i}tre-Robertson-Walker (FLRW) geometry, we present a nonsingular model (no big bang singularity at finite time) of our universe describing its evolution starting from its early inflationary era…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Jaume de Haro , Jaume Amorós , Supriya Pan

In this paper we consider the $\alpha-$attractor model and study inflation under a non-slow-roll dynamics. More precisely, we follow the approach recently proposed by Gong and Sasaki \cite{Gong:2015ypa} by means of assuming…

General Relativity and Quantum Cosmology · Physics 2016-04-05 K. Sravan Kumar , João Marto , Paulo Vargas Moniz , Suratna Das
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