English
Related papers

Related papers: On the inflationary flow equations

200 papers

In this paper, we use a known duality between expanding and contracting cosmologies to construct a dual of the inflationary flow hierarchy applicable to contracting cosmologies such as Ekpyrotic and Cyclic models. We show that the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 William H Kinney , Azadeh Moradinezhad Dizgah

We consider an inflationary scenario where the rate of inflaton roll defined by $\ddot\phi/H\dot \phi$ remains constant. The rate of roll is small for slow-roll inflation, while a generic rate of roll leads to the interesting case of…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-09 Hayato Motohashi , Alexei A. Starobinsky , Jun'ichi Yokoyama

In this work, focused on the production of exact inflationary solutions using dimensional analysis, it is shown how to explain inflation from a pragmatic and basic point of view, in a step-by-step process, starting from the one-dimensional…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sandro Silva e Costa

The framework of a kind of noncanonical warm inflation is introduced, and the dynamical equations of this scenario are presented. We propose the slow roll approximations and give some redefining slow roll parameters in this scenario which…

General Relativity and Quantum Cosmology · Physics 2021-01-13 Xiao-Min Zhang , Ang Fu , Kai Li , Qian Li , Peng-Cheng Chu , Hong-Yang Ma , Jian-Yang Zhu

We revisit the time evolution of a flat and non-flat direction system during inflation. In order to take into account quantum noises in the analysis, we base on stochastic formalism and solve coupled Langevin equations numerically. We focus…

High Energy Physics - Phenomenology · Physics 2015-06-05 Masahiro Kawasaki , Tomohiro Takesako

The article describes various aspects of mathematical modeling of fluid flows, both in general and with reference to hydraulic machinery. The article reviews historical development of corresponding methods of mathematical modeling.…

Fluid Dynamics · Physics 2007-05-23 Alexey N. Kochevsky , Victor G. Nenya

In this paper we revisit the relationship between the Einstein--Friedman and the Abel equations to demonstrate how it might be applied to the inflationary analysis in a flat Friedman universe filled with a real-valued scalar field. The…

General Relativity and Quantum Cosmology · Physics 2019-07-30 Anna V. Yaparova , Artyom V. Yurov , Valerian A. Yurov

In this work, we systematically present a new dynamical systems approach to standard inflationary processes and their variants as constant-roll inflation. Using the techniques presented in our work one can in general investigate the…

General Relativity and Quantum Cosmology · Physics 2026-01-13 Sandip Biswas , Saddam Hussain , Kaushik Bhattacharya

We review locked inflation and we critically address phenomenological and consistency issues thathave appeared in the literature. A natural window of opportunity is found for the original scenario.Moreover, a simple way to enlarge the…

General Relativity and Quantum Cosmology · Physics 2020-01-30 Michael Zantedeschi

The slow-roll approximation is the usual starting point to study the constraints imposed on the inflaton potential parameters by the observational data. We show that, for a potential exhibiting at least two extrema and giving rise to a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Tiago Charters , Jose P. Mimoso , Ana Nunes

We investigate a one dimensional flow described with the non-compressible coupled Euler and non-compressible Navier-Stokes equations in Cartesian coordinate systems. We couple the two fluids through the continuity equation where different…

Fluid Dynamics · Physics 2021-09-28 I. F. Barna , Mátyás László

We develop efficient algorithms for a fundamental network design problem arising in potential-based flow models, which are central to many energy transport networks (e.g., hydrogen and electricity). In contrast to classical network flow…

Discrete Mathematics · Computer Science 2026-04-30 Max Klimm , Marc E. Pfetsch , Martin Skutella , Lea Strubberg

The slow roll approximation is studied for cosmological models in Hyperextended Scalar-Tensor Theories of Gravity. A procedure to obtain slow roll solutions in non-minimally coupled gravity is outlined and some examples are provided. An…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Diego F. Torres

We propose functional approach to the stochastic inflationary universe dynamics. It is based on path integral representation of the solution to the differential equation for the scalar field probability distribution. In the saddle-point…

General Relativity and Quantum Cosmology · Physics 2010-01-15 Yuri V. Shtanov

We study constant-roll inflation using the $\beta$-function formalism. We show that the constant rate of the inflaton roll is translated into a first order differential equation for the $\beta$-function which can be solved easily. The…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-09 F. Cicciarella , J. Mabillard , M. Pieroni

A brief review of inflation is presented. After having demonstrated the generality of the inflationary mechanism, the emphasize is put on its simplest realization, namely the single field slow-roll inflationary scenario. Then, it is shown…

Astrophysics · Physics 2007-05-23 Jerome Martin

In this paper we present a path integral formulation of stochastic inflation, in which volume weighting can easily be implemented. With an in-depth study of inflation in a quartic potential, we investigate how the inflaton evolves and how…

High Energy Physics - Theory · Physics 2013-05-29 Steven Gratton

It is now understood that inflation dynamics comes in two forms, isentropic or cold inflation and nonisentropic or warm inflation. In the former, inflation occurs without radiation production, whereas in the latter both radiation production…

High Energy Physics - Phenomenology · Physics 2007-05-23 Arjun Berera

This paper proposes a new non-oscillatory {\em energy-splitting} conservative algorithm for computing multi-fluid flows in the Eulerian framework. In comparison with existing multi-fluid algorithms in literatures, it is shown that the mass…

Fluid Dynamics · Physics 2018-04-04 Xin Lei , Jiequan Li

Stochastic effects in multi-field inflationary scenarios are investigated. A hierarchy of diffusion equations is derived, the solutions of which yield moments of the numbers of inflationary $e$-folds. Solving the resulting partial…

High Energy Physics - Theory · Physics 2016-08-24 Hooshyar Assadullahi , Hassan Firouzjahi , Mahdiyar Noorbala , Vincent Vennin , David Wands