English
Related papers

Related papers: Hypernatural inflation

200 papers

Inflationary $\alpha$-attractor models in supergravity, which provide excellent fits to the latest observational data, are based on the Poincare disk hyperbolic geometry. We refine these models by constructing Kahler potentials with…

High Energy Physics - Theory · Physics 2015-09-23 John Joseph M. Carrasco , Renata Kallosh , Andrei Linde

We study the dynamics of axion-like fields in F-theory and suggest that they can serve as inflatons in models of natural inflation. The axions arise from harmonic three-forms on the F-theory compactification space and parameterize a complex…

High Energy Physics - Theory · Physics 2021-12-21 Thomas W. Grimm

We propose a natural inflation model driven by an imaginary or axionic component of a K\"ahler modulus in string-inspired supergravity. The shift symmetry of the axion is gauged under an anomalous $U(1)_X$ symmetry, which leads to a…

High Energy Physics - Theory · Physics 2015-06-19 Tianjun Li , Zhijin Li , Dimitri V. Nanopoulos

We construct a natural inflation model in supergravity where the inflaton is identified with a modulus field possessing a shift symmetry. The superpotential for the inflaton is generated by meson condensation due to strong dynamics with…

High Energy Physics - Phenomenology · Physics 2015-06-22 Keisuke Harigaya , Masahiro Ibe , Tsutomu T. Yanagida

We study a particular version of the theory of cosmological $\alpha$-attractors with $\alpha=1/3$, in which both the dilaton (inflaton) field and the axion field are light during inflation. The kinetic terms in this theory originate from…

High Energy Physics - Theory · Physics 2018-04-10 Ana Achúcarro , Renata Kallosh , Andrei Linde , Dong-Gang Wang , Yvette Welling

We discuss inflation models within supersymmetry and supergravity frameworks with a landscape of chiral superfields and one $U(1)$ shift symmetry which is broken by non-perturbative symmetry breaking terms in the superpotential. We label…

High Energy Physics - Phenomenology · Physics 2018-04-18 Pran Nath , Maksim Piskunov

Supergravity models of natural inflation and its generalizations are presented. These models are special examples of the class of supergravity models proposed in arXiv:1008.3375 and arXiv:1011.5945, which have a shift symmetric K\"ahler…

High Energy Physics - Theory · Physics 2014-09-05 Renata Kallosh , Andrei Linde , Bert Vercnocke

We discuss two-stage dilaton-axion inflation models [1] and describe $\alpha$-attractor models with either exponential or polynomial approach to the plateau. We implement one of the models of primordial black hole production proposed in [2]…

High Energy Physics - Theory · Physics 2022-08-31 Renata Kallosh , Andrei Linde

We explore the dynamics of multi-field models of inflation in which the field-space metric is a hyperbolic manifold of constant curvature. Such models are known as $\alpha$-attractors and their single-field regimes have been extensively…

High Energy Physics - Theory · Physics 2021-12-14 Perseas Christodoulidis , Diederik Roest , Evangelos I. Sfakianakis

Multiple axions form a landscape in the presence of various shift symmetry breaking terms. Eternal inflation populates the axion landscape, continuously creating new universes by bubble nucleation. Slow-roll inflation takes place after the…

High Energy Physics - Phenomenology · Physics 2015-04-14 Tetsutaro Higaki , Fuminobu Takahashi

We study an inflationary model developed by Kaloper and Sorbo, in which the inflaton is an axion with a sub-Planckian decay constant, whose potential is generated by mixing with a topological 4-form field strength. This gives a 4d…

High Energy Physics - Theory · Physics 2011-03-18 Nemanja Kaloper , Albion Lawrence , Lorenzo Sorbo

Inflationary $\alpha$-attractor models can be naturally implemented in supergravity with hyperbolic geometry. They have stable predictions for observables, such as $n_s=1-{2/ N_e} $, assuming that the potential in terms of the original…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Renata Kallosh , Andrei Linde

We propose a landscape of many axions, where the axion potential receives various contributions from shift symmetry breaking effects. We show that the existence of the axion with a super-Planckian decay constant is very common in the axion…

High Energy Physics - Theory · Physics 2014-07-22 Tetsutaro Higaki , Fuminobu Takahashi

The $SL(2,\mathbb{Z})$ invariant $\alpha$-attractor models have plateau potentials with respect to the inflaton and axion fields. The potential in the axion direction is almost exactly flat during inflation, hence, the axion field remains…

High Energy Physics - Theory · Physics 2025-06-10 John Joseph Carrasco , Renata Kallosh , Andrei Linde , Diederik Roest

The potential during inflation must be very flat in, at least, the direction of the inflaton. In renormalizable global supersymmetry, flat directions are ubiquitous, but they are not preserved in a generic supergravity theory. It is known…

High Energy Physics - Theory · Physics 2009-09-29 Mary K. Gaillard , David H. Lyth , Hitoshi Murayama

We propose a new class of natural inflation models based on a hidden scale invariance. In a very generic Wilsonian effective field theory with an arbitrary number of scalar fields, which exhibits scale invariance via the dilaton, the…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Neil D. Barrie , Archil Kobakhidze , Shelley Liang

In models of natural inflation, the inflaton is an axion-like particle. Unfortunately, axion potentials in UV-complete theories appear to be too steep to drive inflation. We show that, even for a steep potential, natural inflation can occur…

High Energy Physics - Theory · Physics 2015-05-14 Mohamed M. Anber , Lorenzo Sorbo

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 consider the gravitational generation of the massive Z-boson field of the standard model, due to the natural breaking of its conformal invariance during inflation. The electroweak symmetry restoration at the end of inflation turns the…

Astrophysics · Physics 2008-11-26 K. Dimopoulos , T. Prokopec , O. Tornkvist , A. C. Davis

We show that the recently proposed multi-natural inflation can be realized within the framework of 4D ${\cal N}=1$ supergravity. The inflaton potential mainly consists of two sinusoidal potentials that are comparable in size, but have…

High Energy Physics - Phenomenology · Physics 2014-06-09 Michael Czerny , Tetsutaro Higaki , Fuminobu Takahashi
‹ Prev 1 2 3 10 Next ›