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Related papers: From stable to unstable anomaly-induced inflation

200 papers

We develop a new class of chaotic inflation models with spontaneously broken conformal invariance. Observational consequences of a broad class of such models are stable with respect to strong deformations of the scalar potential. This…

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

We consider an inflationary scenario where the rate of inflaton roll defined by $\ddot\phi/H\dot \phi$ remains constant. The rate of roll is small for slow-roll inflation, while a generic rate of roll leads to the interesting case of…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-09 Hayato Motohashi , Alexei A. Starobinsky , Jun'ichi Yokoyama

In quintessential inflationary model, the same master field that drives inflation becomes, later on, the dynamical source of the (present) accelerated expansion. Quintessential inflationary models require a curvature scale at the end of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Massimo Giovannini

We consider curved space quantum corrections to the equations of motion of the inflaton field in the early Universe. Using the stochastic formalism in phase space, we demonstrate that the quantum corrected evolution of the inflaton can…

High Energy Physics - Phenomenology · Physics 2009-09-25 Zygmunt Lalak , Rudolf Poppe

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

We study several extensions of the Starobinsky model of inflation, which obey all observational constraints on the inflationary parameters, by demanding that both the inflaton scalar potential in the Einstein frame and the $F(R)$ gravity…

General Relativity and Quantum Cosmology · Physics 2022-03-30 Vsevolod R. Ivanov , Sergei V. Ketov , Ekaterina O. Pozdeeva , Sergey Yu. Vernov

Quantum gravitational back-reaction offers the potential of simultaneously resolving the problem of the cosmological constant and providing a natural model of inflation in which scalars play no special role. In this model inflation begins…

Astrophysics · Physics 2007-05-23 R. P. Woodard

During inflation explicit perturbative computations of quantum field theories which contain massless, non-conformal fields exhibit secular effects that grow as powers of the logarithm of the inflationary scale factor. Starobinskii's…

General Relativity and Quantum Cosmology · Physics 2009-11-11 N. C. Tsamis , R. P. Woodard

A continuous process of creation of particles is investigated as a possible connection between the inflationary stage with late cosmic acceleration. In this model, the inflationary era occurs due to a continuous and fast process of creation…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Rafael C. Nunes

We point out that the ability of some models of inflation, such as Higgs inflation and the universal attractor models, in reproducing the available data is due to their relation to the Starobinsky model of inflation. For large field values,…

High Energy Physics - Theory · Physics 2014-03-05 Alex Kehagias , Azadeh Moradinezhad Dizgah , Antonio Riotto

We consider an O(N) model coupled self-consistently to gravity in the semiclassical approximation, where the field is subject to `new inflation' type initial conditions. We study the dynamics self-consistently and non-perturbatively with…

High Energy Physics - Phenomenology · Physics 2011-04-15 D. Boyanovsky , D. Cormier , H. J. de Vega , R. Holman , S. P. Kumar

Higher-order theories of gravity are a branch of modified gravity wherein the geometrodynamics of the four-dimensional Riemannian manifold is determined by field equations involving derivatives of the metric tensor of order higher than two.…

General Relativity and Quantum Cosmology · Physics 2024-04-19 R. R. Cuzinatto , L. G. Medeiros

The energy and time scales during the inflationary stage of the universe calls for an out of equilibrium quantum field treatment. Moreover, the high energy densities involved make necessary the use of non-perturbative approaches as large N…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Boyanovsky , D. Cormier , H. J. de Vega , R. Holman , S. P. Kumar

This paper investigates Starobinsky's model of inflation driven by the trace anomaly of conformally coupled matter fields. This model does not suffer from the problem of contrived initial conditions that occurs in most models of inflation…

High Energy Physics - Theory · Physics 2009-10-31 S. W. Hawking , T. Hertog , H. S. Reall

Hybrid Higgs inflation model is a hybrid type of the so-called Higgs inflation model with the conventional non-minimal $\xi$ coupling to a scalar curvature $R$ and new Higgs inflation model with the derivative coupling to the Einstein…

General Relativity and Quantum Cosmology · Physics 2020-05-20 Seiga Sato , Kei-ichi Maeda

A model of cosmological inflation is proposed in which field space is a hyperbolic plane. The inflaton never slow-rolls, and instead orbits the bottom of the potential, buoyed by a centrifugal force. Though initial velocities redshift away…

High Energy Physics - Theory · Physics 2019-01-03 Adam R. Brown

In this work, we study the effects on the relevant observational parameters of an inflationary universe from a chaotic potential with a step. We numerically evolve the perturbation equations within both cold inflation and warm inflation. On…

General Relativity and Quantum Cosmology · Physics 2023-03-09 Clara Rojas , Rafael Hernández-Jiménez

Working in the Large Volume Scenario (LVS) of IIB Calabi-Yau flux compactifications, we construct inflationary models from recently computed higher derivative $(\alpha')^3$-corrections. Inflation is driven by a Kaehler modulus whose…

High Energy Physics - Theory · Physics 2016-01-08 Benedict J. Broy , David Ciupke , Francisco G. Pedro , Alexander Westphal

Cosmological models with inflation and those with bounce have their own strengths and weaknesses. Here we construct a model in which a phase of bounce is followed by a viable inflationary phase. This incorporates several advantages of both…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-02 Manjeet Kaur , Debottam Nandi , Debajyoti Choudhury , T. R. Seshadri

We study chaotic inflation driven by a real, massive, homogeneous minimally coupled scalar field in a flat Robertson-Walker spacetime. The semiclassical limit for gravity is considered, whereas the scalar field is treated quantum…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Finelli , G. P. Vacca , G. Venturi