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Related papers: Observational constraints on K-inflation models

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Planck data robustly exclude the simple $\lambda\phi^4$ scenario for inflation. This is also the case for models of Axion Inflation in which the inflaton field is the radial part of the Peccei-Quinn complex scalar field. In this letter we…

High Energy Physics - Phenomenology · Physics 2019-08-07 Andrea Caputo

In this paper we develop the formalism for the stochastic approach to inflation at all order in slow-roll parameters. This is done by including the momentum and Hamiltonian constraints into the stochastic equations. We then specialise to…

General Relativity and Quantum Cosmology · Physics 2022-02-09 Diego Cruces , Cristiano Germani

In models like axion monodromy, temporal features during inflation which are not associated with its ending can produce scalar, and to a lesser extent, tensor power spectra where deviations from scale-free power law spectra can be as large…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-31 Hayato Motohashi , Wayne Hu

We examine the power-law Starobinsky model, a generalized version of the Starobinsky inflation model, characterized by a power-law correction to Einstein gravity. Employing the $f(R)$ formalism, the scalar and tensor power spectra were…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-10 Saisandri Saini , Akhilesh Nautiyal

To unlock the vast potential of the CMB trispectrum, we require both robust estimators and efficient computational tools. In this work, we introduce the public code PolySpec: a suite of quartic estimators designed to measure the amplitudes…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-30 Oliver H. E. Philcox

We consider the non-supersymmetric models of chaotic (driven by a quadratic potential) and hybrid inflation, taking into account the minimal possible radiative corrections to the inflationary potential. We show that two simple coupling…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 C. Pallis

We investigate slow-roll inflation within the framework of Kaniadakis and dual Kaniadakis cosmology, where the usual entropy formalism is generalized through a deformation parameter $\kappa$. By deriving the modified Friedmann equations and…

General Relativity and Quantum Cosmology · Physics 2026-05-19 Leila Liravi , Ahmad Sheykhi

We derive the general formulae for the the scalar and tensor spectral tilts to the second order for the inflationary models with non-minimally derivative coupling without taking the high friction limit. The non-minimally kinetic coupling to…

General Relativity and Quantum Cosmology · Physics 2017-02-08 Nan Yang , Qin Fei , Qing Gao , Yungui Gong

The advent of high-precision cosmological observations has challenged many traditional inflationary models. Data from $Planck$ 2018 along with the BICEP/$Keck$ 2018 result have already ruled out most of the established models by placing…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Biswajit Deb , Atri Deshamukhya

We investigate the dynamics of homogeneous phase space for single-field models of inflation. Inflationary trajectories are formally attractors in phase space, but since in practice not all initial conditions lead to them, some degree of…

High Energy Physics - Theory · Physics 2014-11-20 Paul Franche , Rhiannon Gwyn , Bret Underwood , Alisha Wissanji

We review the attractor properties of the simplest chaotic model of inflation, in which a minimally coupled scalar field is endowed with a quadratic scalar potential. The equations of motion in a flat Friedmann-Robertson-Walker universe are…

Astrophysics · Physics 2009-06-23 L. Arturo Urena-Lopez , Mayra J. Reyes-Ibarra

Inflation models can be examined by the cosmological observations, WMAP, Planck, BICEP2 and so on. These observations directly constrain the spectral index, $n_s$, and the tensor-to-scalar ratio, $r$. Besides, from a theoretical point of…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Tomohiro Inagaki , Ryota Nakanishi , Sergei D. Odintsov

In this paper we will illustrate how to constrain unavoidable K\"ahler corrections for ${\cal N}=1$ supergravity (SUGRA) inflation from the recent Planck data. We will show that the non-renormalizable K\"ahler operators will induce in…

High Energy Physics - Theory · Physics 2014-04-15 Sayantan Choudhury , Anupam Mazumdar , Ernestas Pukartas

We present cosmological constraints from Planck 2015 data for a universe that is kinetically dominated at very early times. We perform a Markov chain Monte Carlo analysis to estimate parameters and use nested sampling to determine the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-10 L. T. Hergt , W. J. Handley , M. P. Hobson , A. N. Lasenby

We study the inflationary dynamics of the universe in the Randall-Sandrum typeII Braneworld model. We consider both an inverse-power law and exponential potentials and apply the Slow-Roll approximation in high energy limit to derive…

General Relativity and Quantum Cosmology · Physics 2014-08-12 M. Bennai , H. Chakir , Z. Sakhi

Through a principal component analysis, we study how accurately CMB observables can constrain inflaton potentials in a model independent manner. We apply the general slow-roll approximation in our analysis where we allow, in contrast to the…

Astrophysics · Physics 2008-11-26 Kenji Kadota , Scott Dodelson , Wayne Hu , Ewan D. Stewart

$k$-inflation represents the most general single-field inflation, in which the perturbations usually obey an equation of motion with a time-dependent sound speed. In this paper, we study the observational predictions of the $k$-inflation by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-19 Tao Zhu , Anzhong Wang , Gerald Cleaver , Klaus Kirsten , Qin Sheng

Here, a single field inflationary model driven by a mutated hilltop potential, a subclass of the hilltop models of inflation, is investigated. To constrain the parameter space, we employ the latest $r-n_{\rm s}$ constraints from Planck…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-11 Iraj Safaei , Soma Heydari , Milad Solbi , Kayoomars Karami

We propose a novel {\it k}-Gauss-Bonnet inflationary model, in which a kinetic term of scalar field is allowed to non-minimally couple to the Gauss-Bonnet topological invariant in the absence of a potential of scalar field. As a result,…

General Relativity and Quantum Cosmology · Physics 2022-02-16 Tuyen M. Pham , Duy H. Nguyen , Tuan Q. Do

The constraints on a general form of the power-law potential and the dissipation coefficient in the framework of warm single field inflation imposed by Planck data will be investigated. {By Considering a quasi-static Universe, besides a…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Zahra Ghadiri , Abdollah Refaei , Ali Aghamohammadi , Haidar Sheikhahmadi