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Related papers: Non-slow-roll dynamics in $\alpha-$attractors

200 papers

We reconsider an inflationary model that inflaton field is non-minimally coupled to gravity. We study parameter space of the model up to the second ( and in some cases third ) order of the slow-roll parameters. We calculate inflation…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Kourosh Nozari , S. Shafizadeh

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

We study slow-roll inflation model controlled by the modular flavor symmetry. In the model, the modulus field plays a role of inflaton and the introduction of the stabilizer field coupled to a modular form in the superpotential produces the…

High Energy Physics - Phenomenology · Physics 2023-07-26 Yoshihiko Abe , Tetsutaro Higaki , Fumiya Kaneko , Tatsuo Kobayashi , Hajime Otsuka

The slow-roll approximation is the usual starting point to study the constraints imposed on the inflaton potential parameters by the observational data. We show that, for a potential exhibiting at least two extrema and giving rise to a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Tiago Charters , Jose P. Mimoso , Ana Nunes

We study anisotropic inflation in non-minimal derivative coupling model where the scalar field non-minimally coupled to the $U(1)$ gauge fields and derivative of the scalar field non-minimally coupled to the Einstein tensor. Within the…

High Energy Physics - Theory · Physics 2022-11-29 Parviz Goodarzi

Recently we identified a new class of (super)conformally invariant theories which allow inflation even if the scalar potential is very steep in terms of the original conformal variables. Observational predictions of a broad class of such…

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

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

Slow-roll inflation can be studied as an effective field theory. The form of the inflaton potential consistent with the data is V(phi) = N M^4 w(phi/[sqrt{N} M_{Pl}]) where phi is the inflaton field, M is the inflation energy scale, and N ~…

Astrophysics · Physics 2007-05-23 D. Boyanovsky , H. J. de Vega , N. G. Sanchez

We study models of modular inflation of the form expected to arise from low energy effective actions of superstring theories. We argue on general grounds that the most likely models of modular slow-roll inflation are small field models in…

High Energy Physics - Theory · Physics 2009-12-15 Ido Ben-Dayan , Ram Brustein , Senarath P. de Alwis

We study the slow-roll inflation models, where the inflaton slow-rolls along a trajectory whose orthogonal directions are lifted by potentials with masses of order the Hubble parameter. In these models large non-Gaussianities can be…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Xingang Chen , Yi Wang

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

In constant-roll inflation, the scalar field that drives the accelerated expansion of the Universe is rolling down its potential at a constant rate. Within this framework, we highlight the relations between the Hubble slow-roll parameters…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-08 Alexandros Karam , Luca Marzola , Thomas Pappas , Antonio Racioppi , Kyriakos Tamvakis

In [arXiv:1102.1513] we introduced an inflationary scenario, Non-Abelian Gauge Field Inflation or gauge-flation for short, in which slow-roll inflation is driven by non-Abelian gauge field minimally coupled to gravity. We present a more…

High Energy Physics - Phenomenology · Physics 2015-03-18 A. Maleknejad , M. M. Sheikh-Jabbari

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 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

Non-abelian gauge field inflation is studied in the context of warm inflation scenario. We introduce this scenario as a mechanism that gives an end for gauge-flation model. Slow-roll parameters and perturbation parameters are presented for…

General Relativity and Quantum Cosmology · Physics 2015-06-17 M. R. Setare , V. Kamali

We derive an $\alpha=1/3$ - attractor potential of slow-roll inflation in the geometric set-up of three intersecting $D7$ branes under $T^6/Z_N$ type of $CY_3$-compactification within type IIB/F theory with some near-conifold regions. The…

High Energy Physics - Theory · Physics 2024-05-01 Arunoday Sarkar , Buddhadeb Ghosh

I generalize the inflationary flow equations of Hoffman and Turner to arbitrary order in slow roll. This makes it possible to study the predictions of slow roll inflation in the full observable parameter space of tensor/scalar ratio $r$,…

Astrophysics · Physics 2009-11-07 William H. Kinney

We present a non-perturbative framework for the dynamics of slow-roll inflation that consistently incorporates quantum corrections, based on an alternative functional renormalisation group (RG) approach. We derive the coupled Friedmann-RG…

High Energy Physics - Theory · Physics 2025-11-10 Jean Alexandre , Lucien Heurtier , Silvia Pla

Inflation near a maximum of the potential is studied when non-local derivative operators are included in the inflaton Lagrangian. Such terms can impose additional sources of friction on the field. For an arbitrary spacetime geometry, these…

High Energy Physics - Theory · Physics 2008-11-26 James E. Lidsey