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A scalar potential obtained from the $D$-term in the Supergravity models, which dominates over $F$ term and is mainly responsible for the inflationary phase in the early universe, is studied. The potential with canonical kinetic terms for…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-18 Rathin Adhikari , Mayukh R. Gangopadhyay , Yogesh

We consider a model of D-term inflation in which the inflaton coincides with the standard Higgs doublet. Non-renormalizable terms are controlled by a discrete R-symmetry of the superpotential. We consider radiative corrections to the scalar…

High Energy Physics - Phenomenology · Physics 2010-05-25 K. Tamvakis

We investigate a class of slow roll inflationary models in the light of the recent Cosmic Microwave Background constraints from Planck 2018, ACT DR6, DESI DR1, and BICEP/\textit{Keck} 2018. The combined dataset favors a higher value of the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Suvashis Maity

In this study, we precisely evaluated the feasibility of the chaotic inflation model within a non-canonical kinetic framework. By applying the slow-roll approximation and imposing constraints on the equilateral non-Gaussianity $f_{\rm…

General Relativity and Quantum Cosmology · Physics 2026-05-19 Wei Yang , Chen-Hao Wu , Ya-Peng Hu

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 consider the simplest extension to the Starobinsky model, by allowing an extra scalar field to help drive inflation. We perform our analysis in the Einstein frame and calculate the power spectra at the end of inflation to second order in…

High Energy Physics - Theory · Physics 2015-10-21 Carsten van de Bruck , Laura Elena Paduraru

We update the constraints on the power spectra of primordial curvature perturbation and tensor perturbation including Planck data 2015 (P15) and recently released BICEP2/Keck data (BK15), Baryon Acoustic Oscillation data and the Type Ia…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Jun Li , Qing-Guo Huang

We study a new inflation potential in the framework of the Randall-Sundrum type 2 Braneworld model. Using the technic developped in(Phys. Rev. D75, 123504 (2007).1), we consider both an monomial and a new inflation potentials and apply the…

High Energy Physics - Theory · Physics 2010-02-02 R. Zarrouki , Z. Sakhi , M. Bennai

The newly released Planck CMB data place tight constraints on slow-roll inflationary models. Some of commonly discussed inflationary potentials are disfavored due mainly to the large tensor-to-scalar ratio. In this paper we show that these…

High Energy Physics - Theory · Physics 2013-12-05 Peng-Xu Jiang , Jian-Wei Hu , Zong-Kuan Guo

In this work, we study early-time inflation within a class of $f(R, \phi, X)$ gravity models under a constant-roll condition. Employing a generalized potential of the form $V(\phi)^\sigma$, we derive expressions for the spectral index $n_s$…

General Relativity and Quantum Cosmology · Physics 2025-10-15 Ali I. Keskin , Mehmet Yaşar , K. Kurt

In this paper we analyze scalar gravitational perturbations on a Robertson-Walker background in the presence of multiple scalar fields that take values on a (geometrically non-trivial) field manifold during slow-roll inflation. For this…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Groot Nibbelink , B. J. W. van Tent

We discuss a general bound on the possibility to realise inflation in any minimal supergravity with F-terms. The derivation crucially depends on the sGoldstini, the scalar field directions that are singled out by spontaneous supersymmetry…

High Energy Physics - Theory · Physics 2015-06-04 Andrea Borghese , Diederik Roest , Ivonne Zavala

The increasingly stringent observational bounds on primordial gravitational waves strongly constrain inflationary model building, favoring scenarios that predict highly suppressed tensor perturbations. While many viable constructions rely…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-11 Panagiotis G. Stavros , Spyros Basilakos , Emmanuel N. Saridakis

We investigate the inflation for the quartic hilltop model via a certain type of modified gravity. Precisely, we analyze the $F(\phi) T$ term in the Einstein's gravity to examine the quartic hilltop inflation model. $T$ is the trace of the…

General Relativity and Quantum Cosmology · Physics 2025-07-28 Feyzollah Younesizadeh , Davoud Kamani

We compare the standard single scalar field inflationary predictions with those of an inflationary phase driven by a tachyon field. A slow-roll formalism is defined for tachyon inflation, and we derive the spectra of scalar and tensor…

High Energy Physics - Theory · Physics 2008-11-26 D. A. Steer , F. Vernizzi

We analyze the impact of breaking diffeomorphism invariance in the inflaton sector. In particular, we consider inflaton models which are invariant under the subgroup of transverse diffeomorphisms and address the possibility of implementing…

General Relativity and Quantum Cosmology · Physics 2026-04-13 Antonio L. Maroto , Prado Martín-Moruno , Miguel Orbaneja-Pérez

In Dirac-Born-Infeld inflation, changes in the sound speed that transiently break the slow roll approximation lead to features in the power spectrum. We develop and test the generalized slow roll approximation for calculating such effects…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 V Miranda , Wayne Hu , Peter Adshead

We propose an extension of the Higgs inflation to the hybrid metric-Palatini gravity, where we introduce non-minimal couplings between Higgs and both the metric-type and the Palatini-type Ricci scalars. We study the inflationary…

High Energy Physics - Theory · Physics 2023-05-30 Minxi He , Yusuke Mikura , Yuichiro Tada

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

The slow-roll approximation to inflation is ultimately justified by the presence of inflationary attractors for the orbits of the solutions of the dynamical equations in phase space. There are many indications that the inflaton field…

General Relativity and Quantum Cosmology · Physics 2011-08-11 Valerio Faraoni