English
Related papers

Related papers: Quartic hilltop inflation revisited

200 papers

In this paper, I present an analytic solution to the equation of motion of the inflaton field in a model of rapid roll inflation with a quartic potential by assuming that the Hubble parameter is a constant during inflation. The result is…

High Energy Physics - Phenomenology · Physics 2019-10-23 Chia-Min Lin

A plethora of inflationary models can produce interesting small-scale phenomenology, such as enhanced scalar fluctuations leading to primordial black hole (PBH) production and large scalar-induced GW. Nevertheless, good models must…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-10 Laura Iacconi , Michael Bacchi , Luiz Filipe Guimarães , Felipe T. Falciano

We compute numerically the reheating temperature due to the gravitational production of conformally coupled superheavy particles during the phase transition from the end of inflation to the beginning of kination in two different…

General Relativity and Quantum Cosmology · Physics 2023-01-03 Jaume de Haro , Llibert Aresté Saló

In this paper we study the reheating constraints on inflationary models considering perturbatively decaying inflaton. Important difference with the existing analysis is the inclusion of explicit decaying dynamics of inflaton during…

High Energy Physics - Theory · Physics 2020-11-05 Debaprasad Maity

We propose a model of inflation with a suitable potential for a single scalar field which falls in the wide class of hilltop inflation. We derive the analytical expressions for most of the physical quantities related to inflation and show…

High Energy Physics - Theory · Physics 2010-01-28 Barun Kumar Pal , Supratik Pal , B. Basu

Analyses of inflation models are usually conducted assuming a specific range---e.g., $N_k \simeq 50-60$--of the number $N_k$ of $e$-folds of inflation. However, the analysis can also be performed by taking into account constraints imposed…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Lingyuan Ji , Marc Kamionkowski

The amplitude of primordial curvature perturbations is enhanced when a radiation bath at a temperature T>H is sustained during inflation by dissipative particle production, which is particularly significant when a non-trivial statistical…

High Energy Physics - Phenomenology · Physics 2014-04-03 Sam Bartrum , Mar Bastero-Gil , Arjun Berera , Rafael Cerezo , Rudnei O. Ramos , Joao G. Rosa

We present a class of non-supersymmetric models in which so-called critical Higgs inflation ($\xi<100$) naturally can be realized without using specific values for Higgs and top quark masses. In these scenarios, the Standard Model (SM)…

High Energy Physics - Phenomenology · Physics 2021-05-18 Heng-Yu Chen , Ilia Gogoladze , Shan Hu , Tianjun Li , Lina Wu

Within an expansion in slow-roll inflation parameters, we derive the complete second-order expressions relating the ratio of tensor to scalar density perturbations and the spectral index of the scalar spectrum. We find that ``corrections''…

Astrophysics · Physics 2009-10-22 Edward W. Kolb , Sharon L. Vadas

We present a general polynomial chaotic inflation model in supergravity, for which the predicted spectral index and tensor-to-scalar ratio can lie within the 1 sigma region allowed by the Planck results. Most importantly, the predicted…

High Energy Physics - Phenomenology · Physics 2015-06-16 Kazunori Nakayama , Fuminobu Takahashi , Tsutomu T. Yanagida

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

The predictions of standard Higgs inflation in the framework of the metric formalism yield a tensor-to-scalar ratio $r \sim 10^{-3}$ which lies well within the expected accuracy of near-future experiments $ \sim 10^{-4}$. When the Palatini…

General Relativity and Quantum Cosmology · Physics 2020-11-04 Ioannis D. Gialamas , Alexandros Karam , Angelos Lykkas , Thomas D. Pappas

After Planck 2013, a broad class of inflationary models called \alpha-attractors was developed which has universal observational predictions. For small values of the parameter \alpha, the models have good consistency with the recent CMB…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-22 Mehdi Eshaghi , Moslem Zarei , Nematollah Riazi , Ahmad Kiasatpour

The latest CMB data from ACT DR6, combined with Planck, DESI, and BICEP/Keck, indicate a slight upward shift in the scalar spectral index, placing several previously favored inflationary models under tension. We study an inflationary…

General Relativity and Quantum Cosmology · Physics 2025-11-26 Z. Ossoulian , T. Golanbari , Kh. Saaidi

Scalar field models of inflation based on a large nonminimal coupling to gravity xi, in particular, Higgs inflation, may violate unitarity at an energy scale ~ M_p / xi << M_p. In this case the model is incomplete at energy scales relevant…

High Energy Physics - Phenomenology · Physics 2010-12-01 Rose N. Lerner , John McDonald

Picking out DBI scalar field as inflation, the slow-rolling inflationary scenario is studied by attributing an exponential time function to scale factor; known as intermediate inflation. The perturbation parameters of the model are…

General Relativity and Quantum Cosmology · Physics 2017-08-15 N. Nazavari , A. Mohammadi , Z. Ossoulian , Kh. Saaidi

The allowed range of parameters for supersymmetric hybrid inflation and its extensions are investigated. The lower bound on the reheat temperature T_r in these models with hierarchical right handed neutrinos is found to be 3*10^7 GeV. (T_r…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. N. Senoguz , Q. Shafi

We investigate a standard minimally-coupled scalar-field inflationary scenario, which is based on a new potential, with suitably generalized plateau features, that leads to extra small tensor-to-scalar ratios. In particular, we consider a…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 Gerasimos Kouniatalis , Emmanuel N. Saridakis

The SUSY hybrid inflation model is found to dissipate radiation during the inflationary period. Analysis is made of parameter regimes in which these dissipative effects are significant. The scalar spectral index, its running, and the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Mar Bastero-Gil , Arjun Berera

We have investigated inflation models that predict a very small value of the tensor-to-scalar ratio, $r$. The spectral index $n_s$, and the tensor-to-scalar ratio $r$, are strictly constrained by the Planck data. $n_s$ and $r$ are sensitive…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-01 Koichi Hirano
‹ Prev 1 3 4 5 6 7 10 Next ›