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Related papers: Starobinsky Inflation and beyond in Einstein-Carta…

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We study the phenomenology of the Higgs-Dilaton model in the context of Einstein-Cartan gravity, focusing on the separate impact of the Holst and Nieh-Yan terms on the inflationary observables. Using analytical and numerical techniques, we…

General Relativity and Quantum Cosmology · Physics 2022-05-18 Matteo Piani , Javier Rubio

We study inflation driven by the Higgs field in the Einstein-Cartan formulation of gravity. In this theory, the presence of the Holst and Nieh-Yan terms with the Higgs field non-minimally coupled to them leads to three additional coupling…

High Energy Physics - Phenomenology · Physics 2021-10-22 Mikhail Shaposhnikov , Andrey Shkerin , Inar Timiryasov , Sebastian Zell

We study a class of early universe cosmological models based on Einstein-Cartan gravity and including a higher derivative term corresponding to a power of the Holst scalar curvature. The resulting effective action is basically given by…

High Energy Physics - Theory · Physics 2024-02-16 Alessandro Di Marco , Emanuele Orazi , Gianfranco Pradisi

In the framework of $F(\mathcal{R},\tilde{\mathcal{R}})$ Einstein-Cartan gravity with an action depending both of the Ricci scalar and the so-called Holst-invariant curvature we consider models that include cubic terms of the latter in the…

General Relativity and Quantum Cosmology · Physics 2025-12-03 Theodoros Katsoulas , Kyriakos Tamvakis

We consider a non-canonic field in the context of Starobinsky inflation. We work in Einstein-frame. In this frame, the gravitational part of the action is equivalent to the Hilbert-Einstein action, plus a scalar field called scalaron. We…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Salomeh Khoeini-Moghaddam

The Starobinsky model, considered in the framework of the Palatini formalism, in contrast to the metric formulation, does not provide us with a model for inflation, due to the absence of a propagating scalar degree of freedom that can play…

General Relativity and Quantum Cosmology · Physics 2018-11-28 I. Antoniadis , A. Karam , A. Lykkas , K. Tamvakis

This paper studies the quantum corrections to the Higgs inflation model in the context of the Einstein-Cartan (E-C) gravity in the large-$ N $ limit with $N$ being the number of real scalar components in Higgs. Recently, it is realized that…

High Energy Physics - Phenomenology · Physics 2024-01-05 Minxi He , Kohei Kamada , Kyohei Mukaida

Within the framework of Einstein-Cartan gravity we consider an action, containing up to quadratic terms of the Ricci scalar and the Holst invariant, coupled non-minimally to a scalar field, including couplings of its derivatives to…

General Relativity and Quantum Cosmology · Physics 2025-06-19 Theodoros Katsoulas , Kyriakos Tamvakis

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 study inflation induced by (power-low) scalar curvature corrections to General Relativity. The class of inflationary scalar potentials $V(\sigma)\sim\exp[n\,\sigma]$, $n$ general parameter, is investigated in the Einsein frame and the…

General Relativity and Quantum Cosmology · Physics 2014-09-22 L. Sebastiani , G. Cognola , R. Myrzakulov , S. D. Odintsov , S. Zerbini

We study a model of inflation in which a scalar field $\chi$ is non-minimally coupled to Starobinsky's $R^2$ gravity. After transforming it to the Einstein frame, a new scalar field, the scalaron $\phi$, will appear and couple to $\chi$…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-21 Shi Pi , Ying-li Zhang , Qing-Guo Huang , Misao Sasaki

The action of loop quantum gravity includes the Holst term and/or the Nieh-Yan term in addition to the Ricci scalar. These terms are expected to couple non-minimally to the Higgs. Thus the Holst and Nieh-Yan terms contribute to the…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-28 Miklos Långvik , Juha-Matti Ojanperä , Sami Raatikainen , Syksy Rasanen

An alternative scenario about the phenomenology of primordial Universe is k-inflation. According to this concept, inflation can be achieved by nonstandard kinetic term of scalar field, namely the inflaton. In this project we focus on…

General Relativity and Quantum Cosmology · Physics 2021-12-01 F. P. Fronimos , S. A. Venikoudis

We study pseudoscalar inflation in the Einstein-Cartan-Palatini (first-order) formulation of gravity while allowing for torsion. We introduce two non-minimal interactions in the gravitational sector: pseudoscalar couplings to the Pontryagin…

General Relativity and Quantum Cosmology · Physics 2026-03-23 Peter Adshead , Suddhasattwa Brahma , Indranil Das

In Cuzinatto et al. [Phys. Rev. D 93, 124034 (2016)], it has been demonstrated that theories of gravity in which the Lagrangian includes terms depending on the scalar curvature $R$ and its derivatives up to order $n$, i.e.…

General Relativity and Quantum Cosmology · Physics 2019-05-07 R. R. Cuzinatto , C. A. M. de Melo , L. G. Medeiros , P. J. Pompeia

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

It is shown that the scalar degree of freedom built-in in the quadratic Weyl-invariant Einstein-Cartan gravity can drive inflation and with predictions in excellent agreement with observations.

General Relativity and Quantum Cosmology · Physics 2025-01-29 Georgios K. Karananas

We generalise Starobinsky's model of inflation to space-times with $D>4$ dimensions, where $D-4$ dimensions are compactified on a suitable manifold. The $D$-dimensional action features Einstein-Hilbert gravity, a higher-order curvature…

High Energy Physics - Theory · Physics 2017-02-28 Santiago Pajón Otero , Francisco G. Pedro , Clemens Wieck

We study the postinflationary dynamics of an Einstein-Cartan-Holst gravity-motivated inflationary scenario, known as Einstein-Cartan pseudoscalaron inflation, coupled to a type-I seesaw extension of the Standard Model with three heavy…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-12 Carlo Di Benedetto , Alessandro Di Marco , Emanuele Orazi , Gianfranco Pradisi

In this work we investigate a inflationary scenario generated by a large scalar field $\phi$ that non-minimally couples to a $f(R)$ modified gravity model. For a Starobinsky's like model, it is found that along a particular flat direction,…

High Energy Physics - Phenomenology · Physics 2017-01-17 Romy H. S. Budhi
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