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Related papers: Inflationary Attractor from Tachyonic Matter

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We develop a consistent analytic approach to determine the conditions under which slow roll inflation can arise when the inflaton is the same scalar field that is responsible for the bounce in Loop Quantum Cosmology (LQC). We find that the…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Anshuman Bhardwaj , Edmund J. Copeland , Jorma Louko

Slow roll reconstruction is derived from the Hamilton-Jacobi formulation of inflationary dynamics. It automatically includes information from sub-leading terms in slow roll, and facilitatesthe inclusion of priors based on the duration on…

Astrophysics · Physics 2009-06-23 Peter Adshead , Richard Easther

This paper revisits the Inflationary scenario within the framework of scalar field models possessing a non-canonical kinetic term. We obtain closed form solutions for all essential quantities associated with chaotic inflation including slow…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-03 Sanil Unnikrishnan , Varun Sahni , Aleksey Toporensky

In standard multi-field models, tachyonic isocurvature perturbations generally indicate the presence of an instability. We revisit the stability of some known counterexamples and show that, in a certain class of models that we call ultra…

High Energy Physics - Theory · Physics 2026-03-04 Ana Achúcarro , Perseas Christodoulidis , Jinn-Ouk Gong , Oksana Iarygina

We investigate the inflationary universe in a theory where two scalar fields non-minimally coupling to the scalar curvature and an extra $R^2$ term exist and the conformal invariance is broken. In particular, the slow-roll inflation is…

High Energy Physics - Theory · Physics 2016-03-01 Kazuharu Bamba

This study concerns the consistency of the tachyon warm inflationary models. A linear stability analysis is performed to find the slow-roll conditions, characterized by the potential slow-roll (PSR) parameters, for the existence of a…

General Relativity and Quantum Cosmology · Physics 2014-02-25 Xiao-Min Zhang , Jian-Yang Zhu

We have recently proposed attractor models for modulus fixing, inflation, supersymmetry breaking and dark energy based on no-scale supergravity. In this paper we develop phenomenological and cosmological aspects of these no-scale attractor…

High Energy Physics - Phenomenology · Physics 2020-09-02 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive , Sarunas Verner

We study the generation of local non-Gaussianity in models of canonical single field inflation when their backgrounds are either attractor or non-attractor. We show that the invariance of inflation under space-time diffeomorphisms can be…

High Energy Physics - Theory · Physics 2023-04-13 Rafael Bravo , Gonzalo A. Palma

We investigate the accuracy of the slow-roll approximation for calculating perturbation spectra generated during inflation. The Hamilton-Jacobi formalism is used to evolve inflationary models with different histories. Models are identified…

Astrophysics · Physics 2010-10-27 Sirichai Chongchitnan , George Efstathiou

A wide variety of vacua, and their cosmological realization, may provide an explanation for the apparently anthropic choices of some parameters of particle physics and cosmology. If the probability on various parameters is weighted by…

High Energy Physics - Theory · Physics 2008-11-26 Lawrence J. Hall , Taizan Watari , T. T. Yanagida

We study an inflation model with a flat scalar potential supported by observations and find that slow-roll inflation can emerge after a quasi-cyclic phase of the Universe, where it undergoes repeated expansions and contractions for a finite…

General Relativity and Quantum Cosmology · Physics 2024-05-16 Hiroki Matsui , Alexandros Papageorgiou , Fuminobu Takahashi , Takahiro Terada

In this work we study slow-roll inflation for a vector-tensor model with massive vector fields non-minimally coupled to gravity. The model under consideration has arbitrary parameters for each geometrical coupling. Taking into account a…

General Relativity and Quantum Cosmology · Physics 2016-12-21 A. Oliveros

The aim of this paper is to provide a more precise description of the paradigm of corpuscular slow-roll inflation, which was previously introduced by Casadio et al. in [1]. Specifically, we start by expanding the Starobinsky theory on a…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Andrea Giugno , Andrea Giusti

We study the stochastic formalism of inflation beyond the usual slow-roll approximation. We verify that the assumptions on which the stochastic formalism relies still hold even far from the slow-roll attractor. This includes demonstrating…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-05 Chris Pattison , Vincent Vennin , Hooshyar Assadullahi , David Wands

The scenario of constant-roll inflation is studied where the inflaton is a scalar field with modified kinetic term, known as non-canonical scalar field. This modification leads to some changes in the slow-roll parameters, and also by taking…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Abolhassan Mohammadi , Khaled Saaidi , Haidar Sheikhahmadi

Multi-field inflation with a curved scalar geometry has been found to support background trajectories that violate the slow-roll, slow-turn conditions and thus have the potential to evade the swampland constraints. In order to understand…

High Energy Physics - Theory · Physics 2020-01-08 Perseas Christodoulidis , Diederik Roest , Evangelos I. Sfakianakis

We investigate the slow-roll inflation in the nonminimal derivative coupling (NDC) model with exponential, quadric, and quartic potentials. It was known that this model provides an enhanced slow-roll inflation induced by gravitationally…

General Relativity and Quantum Cosmology · Physics 2015-10-14 Yun Soo Myung , Taeyoon Moon , Bum-Hoon Lee

We consider tachyonic warm-inflationary models in the context of intermediate inflation. We derive the characteristics of this model in slow-roll approximation and develop our model in two cases, 1- For a constant dissipative parameter…

High Energy Physics - Theory · Physics 2015-06-11 M. R. Setare , V. Kamali

In the scalar-tensor theory of gravitation it seems nontrivial to establish if solutions of the cosmological equations in the presence of a cosmological constant behave as attractors independently of the initial values. We develop a general…

High Energy Physics - Theory · Physics 2009-11-06 Kei-ichi Maeda , Yasunori Fujii

Inflationary cosmology attempts to provide a natural explanation for the flatness and homogeneity of the observable universe. In the context of reversible (unitary) evolution, this goal is difficult to satisfy, as Liouville's theorem…

High Energy Physics - Theory · Physics 2010-07-09 Sean M. Carroll , Heywood Tam
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