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Related papers: 1D Supergravity FLRW Model of Starobinsky

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We investigate the cosmological inflation in a class of supergravity models that are generalizations of non-supersymmetric $R^2$ models. Although such models have been extensively studied recently, especially after the launch of the PLANCK…

High Energy Physics - Theory · Physics 2015-06-23 G. A. Diamandis , B. C. Georgalas , K. Kaskavelis , P. Kouroumalou , A. B. Lahanas , G. Pavlopoulos

We show that $R^2$ gravity coupled conformally to scalar fields is equivalent to the real bosonic sector of SU(N,1)/SU(N)$\times$U(1) no-scale supergravity, where the conformal factor can be identified with the K\"ahler potential, and we…

High Energy Physics - Theory · Physics 2018-03-07 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive

The Starobinsky model of cosmological inflation in four spacetime dimensions is reviewed with the emphasis on impact of quantum gravity corrections. As a specific example of the quantum corrections, the Grisaru-Zanon quartic curvature terms…

General Relativity and Quantum Cosmology · Physics 2025-01-09 Shunsuke Toyama , Sergei V. Ketov

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

We have presented previously a general treatment of Starobinsky-like inflation in no-scale supergravity where the tensor-to-scalar ratio $r = 3(1 - n_s)^2$, and $n_s$ is the tilt of the scalar perturbations. In particular, we have shown how…

High Energy Physics - Theory · Physics 2019-10-02 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive , Sarunas Verner

We develop an inflationary model without small parameters on the basis of multidimensional $f(R)$ gravity with a minimally coupled scalar field. The model is described by two stages of space expansion. The first one begins at energy scales…

General Relativity and Quantum Cosmology · Physics 2022-11-22 Polina Petriakova , Sergey G. Rubin

We review the new theory of modified supergravity, dubbed F(\cal R) supergravity, and some of its recent applications to inflation and reheating in the early universe cosmology. The F(\cal R) supergravity is the N=1 locally supersymmetric…

High Energy Physics - Theory · Physics 2013-06-18 Sergei V. Ketov

We present novel implementations of Starobisky-like inflation within Supergravity adopting Kaehler potentials for the inflaton which parameterize hyperbolic geometries known from the T-model inflation. The associated superpotentials are…

High Energy Physics - Phenomenology · Physics 2025-03-07 C. Pallis

We consider the effective evolution of a phenomenological model from FLRW supersymmetric quantum cosmology with a scalar field. The scalar field acts as a clock and inflaton. We examine a family of simple superpotentials that produce an…

General Relativity and Quantum Cosmology · Physics 2022-08-17 N. E. Martínez-Pérez , C. Ramírez , V. M. Vázquez Báez

We present a unified treatment of cosmic inflation within the framework of Myrzakulov Gravity, exploring its realization in three different formalisms: metric (curvature-based), teleparallel (torsion-based), and symmetric teleparallel…

General Relativity and Quantum Cosmology · Physics 2025-07-17 Davood Momeni , Ratbay Myrzakulov

Measurements of the cosmic microwave background (CMB) favour models of inflation with a small tensor-to-scalar ratio r, as predicted by the Starobinsky R + R^2 model. It has been shown previously that various models based on no-scale…

High Energy Physics - Theory · Physics 2019-08-07 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive , Sarunas Verner

Using a no-scale supergravity framework, we construct an SO(10) model that makes predictions for cosmic microwave background observables similar to those of the Starobinsky model of inflation, and incorporates a double-seesaw model for…

High Energy Physics - Phenomenology · Physics 2016-11-15 John Ellis , Marcos A. G. Garcia , Natsumi Nagata , Dimitri V. Nanopoulos , Keith A. Olive

The Starobinsky model of inflation, consistent with Planck 2015, has a peculiar form of the action, which contains the leading Einstein term $R$, the $R^2$ term with a huge coefficient, and negligible higher-order terms. We propose an…

High Energy Physics - Theory · Physics 2016-12-13 Takehiko Asaka , Satoshi Iso , Hikaru Kawai , Kazunori Kohri , Toshifumi Noumi , Takahiro Terada

The idea of gauge theories of gravity predicts that there should exist not only the massless graviton but also massive particles carrying the gravitational force. We study the cosmology in a quadratic gravity with dynamical torsion where…

High Energy Physics - Theory · Physics 2020-06-17 Katsuki Aoki , Shinji Mukohyama

An extension of the Starobinsky model is proposed. Besides the usual Starobinsky Lagrangian, a term proportional to the derivative of the scalar curvature, $\nabla_{\mu}R\nabla^{\mu}R$, is considered. The analyzis is done in the Einstein…

General Relativity and Quantum Cosmology · Physics 2019-03-04 R. R. Cuzinatto , L. G. Medeiros , P. J. Pompeia

We point out that in the large field regime, the recently proposed superconformal D-term inflation model coincides with the Starobinsky model. In this regime, the inflaton field dominates over the Planck mass in the gravitational kinetic…

High Energy Physics - Theory · Physics 2015-06-16 W. Buchmuller , V. Domcke , K. Kamada

We propose a four-dimensional N = 1 supergravity-based Starobinsky-type inflationary model in terms of a single massive vector multiplet, whose action includes the Dirac-Born-Infeld-type kinetic terms and a generalized (new)…

High Energy Physics - Theory · Physics 2018-10-08 Hiroyuki Abe , Yermek Aldabergenov , Shuntaro Aoki , Sergei V. Ketov

The Starobinsky model was born in a cosmological scenario where conformally coupled matter quantum field fluctuations on the vacuum drive a non trivial semiclassical energy momentum tensor quadratic in curvature. The presence of an unstable…

High Energy Physics - Theory · Physics 2025-02-20 Roberto Percacci , Gian Paolo Vacca

Starobinsky's $R+\alpha R^2$ inflation provides a compelling one-parameter inflationary model that is supported by current cosmological observations. However, at the same order in spacetime derivatives as the $R^2$ term, an effective theory…

General Relativity and Quantum Cosmology · Physics 2025-12-03 Eugenio Bianchi , Mauricio Gamonal

We consider an extension of the Starobinsky model, whose parameters are functions of an extra scalar field. Our motivation is to test the robustness (or sensitivity) of the Starobinsky inflation against mixing scalaron with another (matter)…

High Energy Physics - Theory · Physics 2016-02-17 Sho Kaneda , Sergei V. Ketov