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Related papers: Inflation from a chaotic potential with a step

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In the present work, we study slow-roll inflation in scalar-tensor gravity theories in the presence of both the non-minimal coupling between the scalar field and curvature, and the Galileon self-interaction of the scalar field. Furthermore,…

General Relativity and Quantum Cosmology · Physics 2021-11-11 Matías López , Giovanni Otalora , Nelson Videla

We compute the 3-point correlation function for a general model of inflation driven by a single, minimally coupled scalar field. Our approach is based on the numerical evaluation of both the perturbation equations and the integrals which…

Astrophysics · Physics 2010-10-27 Xingang Chen , Richard Easther , Eugene A. Lim

We consider slow-roll inflation in the context of recently proposed four-dimensional effective gravity induced on the world-volume of a three-brane in five-dimensional Einstein gravity. We find significant modifications of the simplest…

High Energy Physics - Phenomenology · Physics 2009-12-30 R Maartens , D Wands , B Bassett , I Heard

This paper presents the CMB angular power spectrum obtained using the \texttt{CAMB} code for three different models of inflation: the Starobinsky inflationary model, the generalized Starobinsky inflationary model, and the chaotic…

General Relativity and Quantum Cosmology · Physics 2024-10-23 Daniel Pozo , Lenin Calvache , Esteban Orozco , Vicente A. Arévalo , Clara Rojas

We consider a quantum deformation of the wave equation on a cosmological background as a toy-model for possible trans-Planckian effects. We compute the power spectrum of scalar and tensor fluctuations for power-law inflation, and find a…

High Energy Physics - Theory · Physics 2009-11-10 Sera Cremonini

There are many single field inflationary models that are consistent with the recent Planck 2018 measurements of the spectral index $n_s$ and tensor-to-scalar ratio $r$. Despite good agreement with observational data some of these models…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-18 Josh Hoffmann , David Sloan

We propose a single field inflationary model by generalizing the inverse power law potential from the intermediate model. We study the implication of our model on the primordial anisotropy of cosmological microwave background radiation.…

High Energy Physics - Theory · Physics 2015-06-17 Zhun Lu

We point out that the prediction of the minimal chaotic inflation model is altered if a scalar field takes a large field value close to the Planck scale during inflation due to a negative Hubble induced mass. In particular, we show that the…

High Energy Physics - Phenomenology · Physics 2016-03-09 Keisuke Harigaya , Masahiro Ibe , Masahiro Kawasaki , Tsutomu T. Yanagida

The measurement of a large tensor-to-scalar ratio by the BICEP2 experiment, r = 0.20 (-0.05)(+0.07), severely restricts the landscape of viable inflationary models and shifts attention once more towards models featuring large inflaton field…

High Energy Physics - Phenomenology · Physics 2015-06-19 Keisuke Harigaya , Masahiro Ibe , Kai Schmitz , Tsutomu T. Yanagida

I discuss folded inflation, an inflationary model embedded in a multi-dimensional scalar potential, such as the stringy landscape. During folded inflation, the field point evolves along a path that turns several corners in the potential.…

High Energy Physics - Theory · Physics 2007-05-23 Richard Easther

Inflation generally assumes a field with nonzero potential that leads to inflationary expansion happening at arbitrarily early times. We demonstrate potentially observable consequences of inflation with a finite initial time in a model in…

High Energy Physics - Theory · Physics 2025-12-05 Rashmish K. Mishra , Michael Nee , Lisa Randall

In the framework of gravitational models obtained from the Geometric Inflation's proposal, where an infinite tower of curvature scalars are included into the action, we compute the slow-roll parameters by the Hubble slow-roll approach. We…

General Relativity and Quantum Cosmology · Physics 2020-09-02 Gustavo Arciniega , Luisa Jaime , Gabriella Piccinelli

The inflationary and pre-inflationary evolution of scalar modes of cosmological perturbations in a closed universe is analyzed for a loop quantum cosmology model with an inflationary regime consistent with the constraints on inflation…

General Relativity and Quantum Cosmology · Physics 2024-11-26 Lucas M. V. Montese , Nelson Yokomizo

We investigate the inflationary expansion of the universe induced by higher curvature corrections in M-theory. The inflationary evolution of the geometry is discussed in ref.[1], thus we succeed to analyse metric perturbations around the…

High Energy Physics - Theory · Physics 2020-09-15 Kazuho Hiraga , Yoshifumi Hyakutake

We explore the inflationary phase of a scalar field with a kinetic term non-minimally coupled to gravity. We find that one of the slow-roll conditions is naturally consequence of the equation of motion of the scalar field. Thus, slow-roll…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-16 Amir Ghalee

Motivated by the result of Planck+BICEP/Keck recently released, we investigate the consistency of the multi-field inflation models in terms of the spectral index $n_s$ and the tensor-to-scalar ratio $r$. In this study, we focus on…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 Yukiyoshi Morishita , Tomo Takahashi , Shuichiro Yokoyama

We consider a warm inflationary scenario in which the two dominant matter components present in the early Universe, the scalar field, and the radiation fluid, evolve with different four-velocities. This cosmological system is mathematically…

General Relativity and Quantum Cosmology · Physics 2021-03-15 Tiberiu Harko , Haidar Sheikhahmadi

We show how observations of the density perturbation (scalar) spectrum and the gravitational wave (tensor) spectrum allow a reconstruction of the potential responsible for cosmological inflation. A complete functional reconstruction or a…

High Energy Physics - Phenomenology · Physics 2009-10-22 Edmund J. Copeland , Edward W. Kolb , Andrew R. Liddle , James E. Lidsey

Scalar fields provide attractive modifications of pre-BBN cosmology, which have interesting implications for dark matter abundances. We analyse the effect of these modifications on the number of e-foldings between horizon exit of CMB modes…

High Energy Physics - Phenomenology · Physics 2018-06-20 Anshuman Maharana , Ivonne Zavala

We revisit the constraints that Planck 2015 temperature, polarization and lensing data impose on the parameters of warm inflation. To this end, we study warm inflation driven by a single scalar field with a quartic self interaction…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-26 Richa Arya , Arnab Dasgupta , Gaurav Goswami , Jayanti Prasad , Raghavan Rangarajan