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Related papers: A viable logarithmic f(R) model for inflation

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We identify models of supersymmetric hybrid inflation in which the tensor-to-scalar ratio, a canonical measure of gravity waves produced during inflation, can be as large as 0.03 or so, which will be tested by the Planck satellite…

High Energy Physics - Phenomenology · Physics 2011-03-07 Qaisar Shafi , Joshua R. Wickman

It is sometimes argued that observation of tensor modes from inflation would provide the first evidence for quantum gravity. However, in the usual inflationary formalism, also the scalar modes involve quantised metric perturbations. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-05 Tommi Markkanen , Syksy Rasanen , Pyry Wahlman

We study the cosmological inflation within the context of f(Q, T) gravity, wherein Q is the nonmetricity scalar and T is the trace of the matter energy-momentum tensor. By choosing a linear combination of Q and T, we first analyze the…

General Relativity and Quantum Cosmology · Physics 2022-08-30 Maryam Shiravand , Saeed Fakhry , Mehrdad Farhoudi

For a robust interpretation of upcoming observations from PLANCK and LHC experiments it is imperative to understand how the inflationary dynamics of a non-minimally coupled Higgs scalar field with gravity may affect the determination of the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 L. A. Popa , A. Caramete

In this paper the focus is on inflationary dynamics in the context of Einstein Gauss-Bonnet gravitational theories. We investigate the implications of the slow-roll condition on the slow-roll indices and we investigate how the inflationary…

General Relativity and Quantum Cosmology · Physics 2018-09-26 S. D. Odintsov , V. K. Oikonomou

In this paper, we discuss inflationary scenario via scalar field and fluid cosmology for anisotropic homogeneous universe model in $f(R)$ gravity. We consider an equation of state which corresponds to quasi-de Sitter expansion and…

General Relativity and Quantum Cosmology · Physics 2018-04-11 M. Sharif , Iqra Nawazish

Realizing the inflationary epoch driven by a pseudo-Nambu Goldstone boson (pNGB) could ensure the coveted flatness, and the sub-Planckian scales related to the dynamics of the paradigm. In this work, we have taken the most general form of…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Hussain Ahmed Khan , Yogesh

We review recent trends on inflationary dynamics in the context of viable modified gravity theories. After providing a general overview of the inflationary paradigm emphasizing on what problems of hot Big Bang theory inflation solves, and a…

General Relativity and Quantum Cosmology · Physics 2023-09-20 S. D. Odintsov , V. K. Oikonomou , I. Giannakoudi , F. P. Fronimos , E. C. Lymperiadou

In this work, we study inflation in a particular scalar-vector-tensor theory of gravitation without the $U(1)$ gauge symmetry. The model is constructed from the more general action introduced in Heisenberg et al. (Phys Rev D 98:024038,…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-20 A. Oliveros , Cristhian J. Rodríguez

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ralf Hofmann , Mathias Th. Keil

We investigate inflationary models in f(R,T) modified gravity with a kinetic coupling term \omega^2 G^{\mu\nu}\partial_{\mu}\phi\partial_{\nu}\phi having a positive factor needed to remove the ghosts. Taking f(R,T)=R+2\beta T, we calculate…

High Energy Physics - Theory · Physics 2023-06-07 A. Belhaj , M. Benali , Y. Hassouni , M. Lamaaoune

One of the fundamental objectives of contemporary cosmology is to understand the physics of the inflationary universe, owing to its observably verifiable predictions about the very early universe with an energy scale of $\sim 10^{16}$ GeV.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Aayush Randeep , Rajib Saha

We study the dynamics of inflation in a generalized scalar-torsion gravity scenario by assuming a canonical scalar field non-minimally coupled to torsion with a Galileon-type self-interaction. After obtaining the field equations for a flat…

General Relativity and Quantum Cosmology · Physics 2019-08-26 Manuel Gonzalez-Espinoza , Giovanni Otalora , Nelson Videla , Joel Saavedra

After reviewing the motivations for cosmological inflation formulated in the formalism of supersymmetry, we argue that the appropriate framework is that of no-scale supergravity. We then show how to construct within this framework…

High Energy Physics - Phenomenology · Physics 2021-02-24 John Ellis , Marcos A. G. Garcia , Natsumi Nagata , Dimitri V. Nanopoulos , Keith A. Olive , Sarunas Verner

Single field inflationary models are investigated within Palatini quadratic gravity represented by $R+\alpha R^2$ along with a non-minimal coupling of the form $f(\phi) R$ between the inflaton field $\phi$ and the gravity. The treatment is…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Mahmoud AlHallak

We study the intermediate inflation scenario in the context of $F(T)$ gravity, and we examine it's viability by calculating the power spectrum of the primordial curvature perturbations and the corresponding spectral index. As we…

General Relativity and Quantum Cosmology · Physics 2017-04-26 V. K. Oikonomou

We consider inflation in a universe with a positive cosmological constant and a nonminimally coupled scalar field, in which the field couples both quadratically and quartically to the Ricci scalar. When considered in the Einstein frame and…

General Relativity and Quantum Cosmology · Physics 2015-08-21 Dražen Glavan , Anja Marunović , Tomislav Prokopec

We present a realistic non-supersymmetric inflation model based on a gauged U(1)$_{B-L}$ symmetry and a tree-level Higgs potential. The inflaton is identified with the scalar field which spontaneously breaks U(1)$_{B-L}$, and we include…

High Energy Physics - Phenomenology · Physics 2013-11-06 Nobuchika Okada , Qaisar Shafi

In [arXiv:1102.1513] we introduced an inflationary scenario, Non-Abelian Gauge Field Inflation or gauge-flation for short, in which slow-roll inflation is driven by non-Abelian gauge field minimally coupled to gravity. We present a more…

High Energy Physics - Phenomenology · Physics 2015-03-18 A. Maleknejad , M. M. Sheikh-Jabbari

In this work, we extend the bottom-up reconstruction framework of $F(R)$ gravity to other modified gravities, and in particular for $f(\phi)R$ and mimetic $F(R)$ gravities. We investigate which are the important conditions in order for the…

General Relativity and Quantum Cosmology · Physics 2018-03-14 S. D. Odintsov , V. K. Oikonomou