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Related papers: Inflation from a Weyl-flat null origin

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We consider slow-roll inflation in the context of a modified Brans-Dicke dilaton gravity. From a two self-interacting potentials $V(\phi)$, we reproduce a Starobinsky-like potential and, commonly in syperstring models, an exponential tail…

General Relativity and Quantum Cosmology · Physics 2024-11-11 Abraão J. S. Capistrano , Gilberto M. Kremer

An axion-like inflaton coupled to non-Abelian gauge bosons provides a compelling microphysical framework for warm inflation. Starting even from cold initial conditions, in these systems, sphaleron heating may generate thermal friction…

High Energy Physics - Phenomenology · Physics 2026-03-16 Mar Bastero-Gil , Pedro García Osorio , António Torres Manso

A study of the slow-roll inflation for an exponential potential in the frame of the scalar-tensor theory is performed, where non-minimal kinetic coupling to curvature and non-minimal coupling of the scalar field to the Gauss-Bonnet…

High Energy Physics - Theory · Physics 2019-09-24 L. N. Granda , D. F. Jimenez

We investigate models in which inflation is driven by an ultraviolet safe and interacting scalar sector stemming from a new class of nonsupersymmetric gauge field theories. These new theories, differently from generic scalar models, are…

High Energy Physics - Phenomenology · Physics 2015-05-22 Niklas Grønlund Nielsen , Francesco Sannino , Ole Svendsen

Inflation in cosmology is a specific stage preceding the Big Bang, aimed at solving both old background problems and new perturbation issues. Single-field inflation is a candidate to illustrate the picture of the initial universe, and…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-21 Guanqiao Liu

We consider a simple model of modified gravity interacting with a single scalar field $\varphi$ with weakly coupled exponential potential within the framework of non-Riemannian spacetime volume-form formalism. The specific form of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-03 David Benisty , Eduardo I. Guendelman , Emil Nissimov , Svetlana Pacheva

A new family of inflation models is introduced and studied. The models are characterised by a scalar potential which, far from the origin, approaches an inflationary plateau in a power-law manner, while near the origin becomes monomial, as…

High Energy Physics - Phenomenology · Physics 2015-11-20 Konstantinos Dimopoulos

It is well known that large Hubble-induced supergravity corrections to the inflaton field can ruin the flatness of the potential, thus creating a tension between slow-roll inflation and supergravity. In this paper we show that it is…

High Energy Physics - Theory · Physics 2012-02-13 Anupam Mazumdar , Seshadri Nadathur , Philip Stephens

Inflection-point inflation is an interesting possibility to realize a successful slow-roll inflation when inflation is driven by a single scalar field with its initial value below the Planck mass ($\phi_I \lesssim M_{Pl}$). In order for a…

High Energy Physics - Phenomenology · Physics 2017-03-08 Nobuchika Okada , Digesh Raut

We determine the frequency of regions of small-field inflation in the Wigner landscape as an approximation to random supergravities/type IIB flux compactifications. We show that small-field inflation occurs exponentially more often than…

High Energy Physics - Theory · Physics 2015-06-15 Francisco G. Pedro , Alexander Westphal

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

We investigate a nonsingular initial state of the Universe which leads to inflation naturally. The model is described by a scalar field with a quadratic potential in Eddington-inspired Born-Infeld gravity. The curvature of this initial…

General Relativity and Quantum Cosmology · Physics 2013-08-26 Inyong Cho , Hyeong-Chan Kim , Taeyoon Moon

We study the effects of the non-attractor initial conditions for the canonical single-field inflation. The non-attractor stage can last only several $e$-folding numbers, and should be followed by hilltop inflation. This two-stage evolution…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-13 Yi-Fu Cai , Jinn-Ouk Gong , Dong-Gang Wang , Ziwei Wang

We investigate all single-field, slow-roll inflationary models whose slow-roll parameters scale as 1/N in the limit of a large number of e-folds N. We proof that all such models belong to two universality classes, characterised by a single…

High Energy Physics - Theory · Physics 2015-06-17 Diederik Roest

We consider initial conditions for inflation in non-minimal kinetic coupling theory. If inflation is driven solely by kinetic term with no potential, the resulting number of e-folds depends only upon initial velocity of the scalar field…

General Relativity and Quantum Cosmology · Physics 2021-09-29 N. Avdeev , A. Toporensky

This study extended noncanonical warm inflation to the nonminimal derivative coupling scenario. The fundamental equations, including the evolution equations and the slow roll equations of this new framework, were derived. The enlarged…

General Relativity and Quantum Cosmology · Physics 2024-12-05 Xiao-Min Zhang , Run-Qing Zhao , Zhi-peng Peng , Xi-Bin Li , Yun-Cai Feng , Peng-Cheng Chu , Yi-Hang Xing

We revisit the problem of the "probability of inflation" from the point of view of the Einstein-Cartan theory, where torsion can be present off-shell even in the absence of spinorial currents. An informal estimate suggests that the barrier…

General Relativity and Quantum Cosmology · Physics 2022-11-23 Emma Albertini , Stephon Alexander , Gabriel Herczeg , Joao Magueijo

The original model of axion natural inflation produces a tensor-to-scalar ratio above the experimental limit. Aligned axion inflation admits inflationary trajectories that originate near a saddle point of the two-field potential, and…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-20 Federico Greco , Marco Peloso

We construct two simple effective field theory versions of {\it Hybrid Natural Inflation (HNI)} that illustrate the range of its phenomenological implications. The resulting inflationary sector potential, $V=\Delta^4(1+a\cos(\phi/f))$,…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Graham G. Ross , Gabriel German , J. Alberto Vazquez

We show that within the framework of a definite proposal for the initial conditions for the universe, the Hartle-Hawking `no boundary' proposal, open inflation is generic and does not require any special properties of the inflaton…

High Energy Physics - Theory · Physics 2009-10-31 S. W. Hawking , Neil Turok