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Related papers: Is Imaginary Starobinsky Model Real?

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Inflationary theory is already 20 years old, and it is impossible to describe all of its versions and implications in a short talk. I will concentrate on several subjects which I believe to be most important. First of all, I will give a…

High Energy Physics - Theory · Physics 2017-02-08 Andrei Linde

When considered in the Palatini formalism, the Starobinsky model does not provide us with a mechanism for inflation due to the absence of a propagating scalar degree of freedom. By (non)--minimally coupling scalar fields to the Starobinsky…

General Relativity and Quantum Cosmology · Physics 2019-03-20 I. Antoniadis , A. Karam , A. Lykkas , T. Pappas , K. Tamvakis

Analytic infinite derivative (AID) non-local quadratic curvature gravity in Weyl basis is known to be ghost free, superrenormalizable or finite and perturbatively Unitary and as such it is Ultra-Violet (UV) complete. Recently $R+R^2$…

High Energy Physics - Theory · Physics 2018-10-08 K. Sravan Kumar , Leonardo Modesto

In this paper we investigate the induced inflation with two flat regions: one Starobinsky-like plateau in big field regime and one shorter plateau around the saddle point of the Einstein frame potential. This multi-phase inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 Michal Artymowski , Zygmunt Lalak , Marek Lewicki

Recent work is reported on inflation model building in the context of supergravity and superstrings, with special emphasis on False Vacuum (`Hybrid') Chaotic Inflation. Globally supersymmetric models do not survive in generic supergravity…

High Energy Physics - Phenomenology · Physics 2009-10-28 David H. Lyth , Ewan D. Stewart

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. Starobinski\u{\i}'s…

Astrophysics · Physics 2009-11-10 R. P. Woodard

We show that a new class of helical phase inflation models can be simply realized in minimal supergravity, wherein the inflaton is the phase component of a complex field and its potential admits a deformed helicoid structure. We find a new…

High Energy Physics - Theory · Physics 2015-10-19 Tianjun Li , Zhijin Li , Dimitri V. Nanopoulos

It has been shown that hybrid inflation may end with the formation of non-topological solitons of inflaton field. As a first step towards a fully realistic picture of the post-inflation era and reheating in supersymmetric hybrid inflation…

High Energy Physics - Phenomenology · Physics 2009-11-10 Matt Broadhead , John McDonald

I describe the first model of chaotic inflation in supergravity, which was proposed by Goncharov and the present author in 1983. The inflaton potential of this model has a plateau-type behavior $V_{0} (1- {8\over 3}\, e^{-\sqrt 6 |\phi|})$…

High Energy Physics - Theory · Physics 2015-06-23 Andrei Linde

Assuming the space dimension is not constant but decreases during the expansion of the Universe, we study chaotic inflation with the potential $m^2 \phi^2/2$. We write down field equations in the slow-roll approximation and define slow…

Astrophysics · Physics 2009-10-31 Forough Nasseri , Sohrab Rahvar

We explore two saddle point inflationary scenarios in the context of higher order corrections related to different generalisations of general relativity. Firstly, we deal with Jordan frame Starobinsky potential, for which we identify a…

High Energy Physics - Theory · Physics 2016-02-17 Michal Artymowski , Zygmunt Lalak , Marek Lewicki

Starobinsky inflation is currently one of the best models concerning agreement with cosmological data. Despite this observational success, it is still lacking a robust embedding into a UV complete theory. Previous efforts to derive…

High Energy Physics - Theory · Physics 2024-01-18 Max Brinkmann , Michele Cicoli , Pietro Zito

With the growing consensus on simple power law inflation models not being favored by the PLANCK observations, dynamics for the non-standard inflation gain significant interest in the recent past. In this paper, we analyze in detail a class…

General Relativity and Quantum Cosmology · Physics 2019-03-08 Debaprasad Maity , Pankaj Saha

We consider a phenomenological extension of the minimal supersymmetric standard model which incorporates chaotic inflation and a radiatively generated intermediate mass scale. Initially a period of chaotic inflation is driven by a quartic…

High Energy Physics - Phenomenology · Physics 2009-10-28 Tony Gherghetta , Gordon L. Kane

This article is dedicated to the memory of Alexei Starobinsky. I begin with some recollections of him and then review the generalization of his wonderful stochastic formalism from scalar potential models to theories which interact with…

General Relativity and Quantum Cosmology · Physics 2025-01-28 R. P. Woodard

The theory of General Relativity was established on a spacetime manifold equipped with a metric tensor, $(\mathcal{M}_4,\text{g})$, and the connection on $\mathcal{M}_4$ identified with the Levi-Civita one. Even though there are valid…

General Relativity and Quantum Cosmology · Physics 2022-02-24 Angelos Lykkas

We show that in the simplest theories of spontaneous symmetry breaking one can have a stage of a fast-roll inflation. In this regime the standard slow-roll condition |m^2| << H^2 is violated. Nevertheless, this stage can be rather long if…

High Energy Physics - Theory · Physics 2009-11-07 Andrei Linde

We propose a version of chaotic inflation, in which a fundamental scale M, well below the Planck scale M_P, fixes the initial value of the effective potential. If this scale happens to be the scale of grand unified theories, there are just…

High Energy Physics - Phenomenology · Physics 2009-12-23 Dominik J. Schwarz , Erandy Ramirez

We discuss how Starobinsky-like inflation may emerge from dilaton dynamics in brane cosmology scenarios based on string theory, in which our universe is represented as a three-brane. The effective potential may acquire a constant term from…

High Energy Physics - Theory · Physics 2015-06-18 John Ellis , Nick E. Mavromatos , Dimitri V. Nanopoulos

We provide a comprehensive numerical study of the Emergent Cyclic Inflation scenario. This is a scenario where instead of traditional monotonic slow roll inflation, the universe expands over numerous short asymmetric cycles due to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 William Duhe , Tirthabir Biswas