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Related papers: Reassessing constant-roll Warm Inflation

200 papers

Constant-roll inflation is a distinctive class of phenomenological inflationary models in which the inflaton's rate of roll remains constant. It provides an exact solution that is compatible with the latest observational constraints and…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-25 Hayato Motohashi

Linking the slow-roll scenario and the Dirac-Born-Infeld scenario of ultra-relativistic roll (where, thanks to the warp factor, the inflaton moves slowly even with an ultra-relativistic Lorentz factor), we find that the KKLMMT D3/anti-D3…

High Energy Physics - Theory · Physics 2010-01-03 Sarah E. Shandera , S. -H. Henry Tye

We point out the existing confusions about the slowroll parameters and conditions for multifield inflation. If one requires the fields to roll down the gradient flow, we find that only articles adopting the Hubble slowroll expansion are on…

High Energy Physics - Theory · Physics 2013-05-30 I-Sheng Yang

A new scenario of hybrid-like inflation is considered without using hybrid-type potential. Radiation raised continuously by a dissipating inflaton field keeps symmetry restoration in a remote sector, and the false-vacuum energy of the…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 Tomohiro Matsuda

We constrain slow-roll inflationary models using the recent WMAP data combined with data from the VSA, CBI, ACBAR and 2dF experiments. We find the slow-roll parameters to be $0 < \epsilon_1 < 0.032$ and $\epsilon_2 + 5.0 \epsilon_1 = 0.036…

Astrophysics · Physics 2009-11-07 Samuel M Leach , Andrew R Liddle

It is presumed that thermal fluctuations present during inflationary epoch can make inflaton scalar field to interact with other fields resulting in the existence of a thermal component during the inflationary period. The presence of this…

General Relativity and Quantum Cosmology · Physics 2022-06-22 Subhra Bhattacharya

Warm inflationary universe models in the context of logamediate expansion are studied. General conditions required for these models to be realizable and discussed. This study is done in the weak and strong dissipative regimes. The…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Ramon Herrera , Marco Olivares

We investigate in detail the attractor behavior of some inflationary models based on braneworld dynamics under the constant-roll condition. We describe the dynamics of the models, assuming that the second slow-roll parameter remains…

General Relativity and Quantum Cosmology · Physics 2025-04-29 Goran S. Djordjevic , Neven Bilić , Dragoljub D. Dimitrijevic , Milan Milosevic , Marko Stojanovic

Ultra-slow-roll (USR) inflation is a new mode of inflation which corresponds to the occasions when the inflaton field must traverse an extremely flat part of the scalar potential, when the usual slow-roll (SR) fails. We investigate USR and…

High Energy Physics - Phenomenology · Physics 2017-12-06 Konstantinos Dimopoulos

In this paper we investigate the inflationary phenomenology of an Einstein-Gauss-Bonnet theory compatible with the GW170817 event, by imposing the constant-roll evolution on the scalar field. We develop the constant-roll GW170817-compatible…

General Relativity and Quantum Cosmology · Physics 2020-09-15 S. D. Odintsov , V. K. Oikonomou , F. P. Fronimos , S. A. Venikoudis

The present work examines the possibility of warm inflationary paradigm in the modified gravity theory with fractal geometry. By choosing the normal fluid as radiation fluid and the effective fluid (with the extra term in modified field…

General Relativity and Quantum Cosmology · Physics 2022-04-14 A. Bose , S. Chakraborty

In this work, we investigate warm inflationary models in the context of a general scalar-tensor theory of gravity which is coupled to radiation through a dissipation term. We first derive the potential of exponential and hyperbolic tangent…

General Relativity and Quantum Cosmology · Physics 2022-04-06 Waluka Amake , Apirak Payaka , Phongpichit Channuie

By extending the potential, we propose a mechanism for the end of the constant-roll inflation and the subsequent reheating phase in the FLRW space-time. Based on astrophysical data, we estimate the Universe reheating temperature.

General Relativity and Quantum Cosmology · Physics 2020-01-22 H. Mohseni Sadjadi , V. Anari

We study a single field inflationary model modified by a non-minimal coupling term between the Ricci scalar $R$ and the scalar field $\varphi$ in the context of constant-roll inflation. The first-order formalism is used to analyse the…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Mehdi Shokri , Jafar Sadeghi , Mohammad Reza Setare , Salvatore Capozziello

In the present paper we study warm inflationary universe models in the context of a polytropic gas. We derive the characteristics of this model in slow-roll approximation and develop our model in two cases, 1- For a constant dissipative…

General Relativity and Quantum Cosmology · Physics 2015-06-16 M. R. Setare , M. J. S. Houndjo , V. Kamali

We develop a consistent analytic approach to determine the conditions under which slow roll inflation can arise when the inflaton is the same scalar field that is responsible for the bounce in Loop Quantum Cosmology (LQC). We find that the…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Anshuman Bhardwaj , Edmund J. Copeland , Jorma Louko

The Wheeler-DeWitt equation provides the probability distribution for the curvature perturbation, the gauge invariant quantum fluctuation of the inflaton. From this, we can find a tower of power spectra which is not found in a perturbative…

High Energy Physics - Theory · Physics 2020-11-09 Min-Seok Seo

It is usually supposed that inflation is of the slow-roll variety, and that the inflaton generates the primordial curvature perturbation. According to the curvaton hypothesis, inflation need not be slow-roll, and if it is the inflaton…

High Energy Physics - Phenomenology · Physics 2009-07-09 Konstantinos Dimopoulos , David H. Lyth

We consider warm inflation with a Dirac-Born-Infeld (DBI) kinetic term in which both the nonequilibrium dissipative particle production and the sound speed parameter slow the motion of the inflaton field. We find that a low sound speed…

High Energy Physics - Theory · Physics 2021-08-19 Meysam Motaharfar , Rudnei O. Ramos

We present an study from PLANCK2013+WP+BAO:$\Lambda$CDM+$r$+$\alpha_s$ data, where 49 slow roll inflationary potentials are tested, showing that the theoretical value of the running provided by 48 of these potentials has a deviation to the…

General Relativity and Quantum Cosmology · Physics 2015-03-24 Jaume Amoros , Jaume de Haro