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Related papers: Stochastic approaches to inflation model building

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We study models of inflation where the inflaton corresponds to a flat direction in field space and its mass term is generated by gravity mediated soft supersymmetry breaking at high scale. Assuming the inflaton to have non negligible…

High Energy Physics - Phenomenology · Physics 2007-05-23 Laura Covi

We examine inflationary universe models driven by scalar fields with logarithmic potentials of the form $V(\phi) = V_0 \phi^p(\ln \phi)^q$. Combining the slow-roll approximation with asymptotic techniques, we identify regions of the…

Astrophysics · Physics 2009-10-28 John D. Barrow , Paul Parsons

We develop a stochastic approach to a non de Sitter Universe in a gauge-invariant way and obtain a system of Langevin-type equations which may be considered to be renormalization group equations for the long wave parts of the scalar fields…

High Energy Physics - Theory · Physics 2008-02-03 Boris Spokoiny

An algorithm is used to generate new solutions of the scalar field equations in homogeneous and isotropic universes. Solutions can be found for pure scalar fields with various potentials in the absence and presence of spatial curvature and…

General Relativity and Quantum Cosmology · Physics 2016-11-23 John D. Barrow , Andronikos Paliathanasis

A method is developed to estimate the properties of a global hydrodynamic instability in turbulent flows from measurement data of the limit-cycle oscillations. For this purpose, the flow dynamics are separated in deterministic contributions…

Fluid Dynamics · Physics 2021-04-21 Moritz Sieber , C. Oliver Paschereit , Kilian Oberleithner

We present and discuss a new approach increasing by orders of magnitude the speed of performing Bayesian inference and parameter estimation within the framework of slow-roll inflation. The method relies on the determination of an effective…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-03 Christophe Ringeval

Data assimilation plays a crucial role in numerical modeling, enabling the integration of real-world observations into mathematical models to enhance the accuracy and predictive capabilities of simulations. This approach is widely applied…

Numerical Analysis · Mathematics 2024-11-08 Alexander Lobbe , Dan Crisan , Oana Lang

Statistical estimation of the prediction uncertainty of physical models is typically hindered by the inadequacy of these models due to various approximations they are built upon. The prediction errors due to model inadequacy can be handled…

Data Analysis, Statistics and Probability · Physics 2017-09-11 Pascal Pernot

We analyze the flow into inflation for generic "single-clock" systems, by combining an effective field theory approach with a dynamical-systems analysis. In this approach, we construct an expansion for the potential-like term in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-15 Feraz Azhar , David I. Kaiser

Stochastic inflation can resolve strong inflationary perturbations, which seed primordial black holes. I present a fast and accurate way to compute these perturbations in typical black hole producing single-field models, treating the…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-25 Eemeli Tomberg

Inflationary cosmology is the leading explanation of the very early universe. Many different models of inflation have been constructed which fit current observational data. In this work theoretical and numerical methods for constraining the…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 Ian Huston

Inflation is a highly favoured theory for the early Universe. It is compatible with current observations of the cosmic microwave background and large scale structure and is a driver in the quest to detect primordial gravitational waves. It…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-19 Tomás Sousa , Deaglan J. Bartlett , Harry Desmond , Pedro G. Ferreira

We provide a formulation of Stochastic Inflation in full general relativity that goes beyond the slow-roll and separate universe approximations. We show how gauge invariant Langevin source terms can be obtained for the complete set of…

General Relativity and Quantum Cosmology · Physics 2024-06-18 Yoann L. Launay , Gerasimos I. Rigopoulos , E. P. S. Shellard

The microscopic quantum field theory origins of warm inflation dynamics are reviewed. The warm inflation scenario is first described along with its results, predictions and comparison with the standard cold inflation scenario. The basics of…

High Energy Physics - Phenomenology · Physics 2009-02-25 Arjun Berera , Ian G. Moss , Rudnei O. Ramos

Some models of clustering processes are formulated and analytically solved employing generating functions methods. Those models include events which result from combined action of the coagulation and fragmentation processes. Fragmentation…

Statistical Mechanics · Physics 2009-11-07 Vladimir M. Dubovik , Arkadi G. Galperin , Viktor S. Richvitsky , Aleksey A. Lushnikov

We introduce ImitationFlow, a novel Deep generative model that allows learning complex globally stable, stochastic, nonlinear dynamics. Our approach extends the Normalizing Flows framework to learn stable Stochastic Differential Equations.…

Machine Learning · Computer Science 2020-10-27 Julen Urain , Michelle Ginesi , Davide Tateo , Jan Peters

We propose a new model-independent mechanism for producing primordial black holes from a period of multi-field inflation. This requires an enhancement of primordial fluctuations at short scales compared to their value at CMB scales. We show…

High Energy Physics - Theory · Physics 2023-04-19 Jacopo Fumagalli , Sébastien Renaux-Petel , John W. Ronayne , Lukas T. Witkowski

Inflationary solutions are constructed in a specific five-dimensional model with boundaries motivated by heterotic M-theory. We concentrate on the case where the vacuum energy is provided by potentials on those boundaries. It is pointed out…

High Energy Physics - Theory · Physics 2016-08-25 Andre Lukas , Burt A. Ovrut , Daniel Waldram

There are hidden observables for inflation, such as features localized in position space, which do not manifest themselves when only one inflation trajectory is considered. To address this issue, we investigate inflation dynamics in a…

High Energy Physics - Theory · Physics 2012-10-02 Francis Duplessis , Yi Wang , Robert Brandenberger

We review the main aspects of the warm inflation scenario, focusing on the inflationary dynamics and the predictions related to the primordial spectrum of perturbations, to be compared with the recent cosmological observations. We study in…

High Energy Physics - Phenomenology · Physics 2010-04-21 Mar Bastero-Gil , Arjun Berera
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