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Related papers: Galileon intermediate inflation

200 papers

We consider the running of the spectral index as a probe of both inflation itself, and of the overall evolution of the very early universe. Surveying a collection of simple single field inflationary models, we confirm that the magnitude of…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Peter Adshead , Richard Easther , Jonathan Pritchard , Abraham Loeb

We study the tachyon inflation in the presence of the superpotential as an inflationary potential. We study the primordial perturbations and their non-gaussian feature in the equilateral configuration. We use the Planck2018 TT, TE,…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-18 Narges Rashidi

A new class of inflation models within the context of G-inflation is proposed, in which the standard model Higgs boson can act as an inflaton thanks to Galileon-like non-linear derivative interaction. The generated primordial density…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-05 Kohei Kamada , Tsutomu Kobayashi , Masahide Yamaguchi , Jun'ichi Yokoyama

We investigate two classes of models of quintessential inflation, based upon canonical as well as noncanonical scalar fields. In particular, introducing potentials steeper than the standard exponential, we construct models that can give…

General Relativity and Quantum Cosmology · Physics 2015-07-17 Chao-Qiang Geng , Md. Wali Hossain , R. Myrzakulov , M. Sami , Emmanuel N. Saridakis

We consider small-field models which invoke the usual framework for the effective field theory, and large-field models which go beyond that. Present and future possibilities for discriminating between the models are assessed, on the…

Astrophysics · Physics 2015-06-24 Laila Alabidi , David Lyth

Inflation in the framework of $f(R)$ modified gravity is revisited. We study the conditions that $f(R)$ should satisfy in order to lead to a viable inflationary model in the original form and in the Einstein frame. Based on these criteria…

High Energy Physics - Theory · Physics 2018-10-17 M. Amin , S. Khalil , M. Salah

We study inflation in the Brans-Dicke gravity as a special model of the scalar-tensor gravity. We obtain the inflationary observables containing the scalar spectral index, the tensor-to-scalar ratio, the running of the scalar spectral index…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-06 B. Tahmasebzadeh , K. Rezazadeh , K. Karami

We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-12 Shinji Tsujikawa , Junko Ohashi , Sachiko Kuroyanagi , Antonio De Felice

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

Gauge-flation is a recently proposed model in which inflation is driven solely by a non-Abelian gauge field thanks to a specific higher order derivative operator. The nature of the operator is such that it does not introduce ghosts. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Ryo Namba , Emanuela Dimastrogiovanni , Marco Peloso

We have realized non-minimal Higgs inflation and standard hybrid inflation in the supersymmetric flipped $SU(5)$ model with $U(1)_R$ symmetry using the no-scale form of the K\"{a}hler potential. In non-minimal Higgs inflation the waterfall…

High Energy Physics - Phenomenology · Physics 2021-10-12 Mian Muhammad Azeem Abid , Maria Mehmood , Mansoor Ur Rehman , Qaisar Shafi

The inflation model with non-minimal coupling scalar field in the context of the hybrid metric Palatini is studied in this paper. We derive the Einstein's field equations, the equations of motion of the scalar field. Furthermore,the…

General Relativity and Quantum Cosmology · Physics 2024-02-29 Brahim Asfour , Aatifa Bargach , Ahmed Errahmani , Taoufik Ouali

We study primordial fluctuations generated during inflation in a class of models motivated by the DBI Galileons, which are extensions of the DBI action that yield second order field equations. This class of models generalises the DBI…

High Energy Physics - Theory · Physics 2010-12-13 Shuntaro Mizuno , Kazuya Koyama

We study inflation in the framework of $f(T)$-gravity in the presence of a canonical scalar field. After reviewing the basic equations governing the background cosmology in $f(T)$-gravity, we turn to study the cosmological perturbations and…

General Relativity and Quantum Cosmology · Physics 2016-02-02 K. Rezazadeh , A. Abdolmaleki , K. Karami

We study generalized Galileons as a framework to develop the most general single-field inflation models ever, Generalized G-inflation, containing yet further generalization of G-inflation, as well as previous examples such as k-inflation,…

High Energy Physics - Theory · Physics 2011-11-03 Tsutomu Kobayashi , Masahide Yamaguchi , Jun'ichi Yokoyama

Tachyon inflationary universe model on the brane in the context of warm inflation is studied. In slow-roll approximation and in longitudinal gauge, we find the primoradial perturbation spectrums for this scenario. We also present the…

General Relativity and Quantum Cosmology · Physics 2016-09-20 Vahid Kamali , Mohammad Reza Setare

We set up cosmological perturbation theory and study the cosmological implications of the so-called ``generalized Galileon'' developed in \cite{Deffayet:2011gz,horndeski}. This is the most general scalar field theory whose Lagrangian…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-26 Xian Gao , Daniele A. Steer

We provide a detailed study of natural inflation with a periodic non-minimal coupling, which is a well-motivated inflationary model that admits an explicit UV completion. We demonstrate that this construction can satisfy the most recent…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-18 Alberto Salvio , Simone Sciusco

Light scalar fields present during inflation can lead to interesting observable signatures, especially in models with non-equilibrium reheating dynamics. We study a supersymmetric hybrid inflation model with a third scalar whose lightness…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-20 Stefano Orani , Arttu Rajantie

In hybrid inflationary models, inflation ends by a sudden instability associated with a steep ridge in the potential. Here we argue that this feature can generate a large contribution to the curvature perturbation on observable scales. This…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-21 David Mulryne , David Seery , Daniel Wesley