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Related papers: It\^o versus Stratonovich in a stochastic cosmolog…

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We develop a simple model to study classical fields on the background of a fluctuating spacetime volume. It is applied to formulate the stochastic Einstein equations with a perfect-fluid source. We investigate the particular case of a…

General Relativity and Quantum Cosmology · Physics 2017-09-06 Vladimir Dzhunushaliev , Hernando Quevedo

In this paper we use the It\^o's formula and comparison theorems to study the blow-up in finite time of stochastic differential equations driven by a Brownian motion. In particular, we obtain an extension of Osgood criterion, which can be…

Probability · Mathematics 2013-05-14 Jorge A. León , Liliana Peralta Hernández , José Villa-Morales

Many physical processes depend on the time it takes a diffusing particle to find a target. Though this classical quantity is now well-understood in various scenarios, little is known if the diffusivity depends on the location of the…

Statistical Mechanics · Physics 2025-12-23 Hwai-Ray Tung , Sean D Lawley

We perturb with an additive Gaussian white noise the Hamiltonian system associated to a cubic anharmonic oscillator. The stochastic system is assumed to start from initial conditions that guarantee the existence of a periodic solution for…

Probability · Mathematics 2019-07-26 Enrico Bernardi , Alberto Lanconelli

Stochastic perturbations of transport type are a common and widely accepted way of representing turbulent effects in fluid dynamics models. In many known examples, it even leads to improved solution theory, a phenomenon known as…

Analysis of PDEs · Mathematics 2025-11-19 Federico Butori , Avi Mayorcas , Silvia Morlacchi

A new approach for arbitrary dimension to the Friedmann cosmological models is presented. Taking suitable changes of the parameters of the spacetime the harmonic motion equations appear, where the curvature determines the angular frequency.…

General Relativity and Quantum Cosmology · Physics 2014-03-03 Rafael M. Rubio , Juan J. Salamanca

We point out that, due to the nonlinearity of the Einstein equations, a homogeneous approximation in cosmology leads to the appearance of an additional term in the Friedmann equation. This new term is associated with the spatial…

Astrophysics · Physics 2015-06-24 Gyula Bene , Viktor Czinner , Matyas Vasuth

Recently, a novel framework to handle stochastic processes has emerged from a series of studies in biology, showing situations beyond 'It\^o versus Stratonovich'. Its internal consistency can be demonstrated via the zero mass limit of a…

Statistical Mechanics · Physics 2012-09-17 Ruoshi Yuan , Ping Ao

The influence of small random perturbations on a deterministic dynamical system with a locally stable equilibrium is considered. The perturbed system is described by the It\^{o} stochastic differential equation. It is assumed that the noise…

Mathematical Physics · Physics 2016-02-18 Oskar Sultanov

In this paper, we consider stochastic Schroedinger equations with two-dimensional white noise. Such equations are used to describe the evolution of an open quantum system undergoing a process of continuous measurement. Representations are…

Mathematical Physics · Physics 2011-08-17 J. Gough , O. O. Obrezkov , O. G. Smolyanov

In view of late-time cosmic acceleration, a dark energy cosmological model is revisited wherein Einstein's cosmological constant is considered as a candidate of dark energy. Exact solution of Einstein field equations (EFEs) is derived in a…

General Relativity and Quantum Cosmology · Physics 2019-11-22 S. K. J. Pacif , Md Salahuddin Khan , L. K. Paikroy , Shalini Singh

We introduce a stochastic analysis of Grassmann random variables suitable for the stochastic quantization of Euclidean fermionic quantum field theories. Analysis on Grassmann algebras is developed here from the point of view of quantum…

Probability · Mathematics 2022-02-02 Sergio Albeverio , Luigi Borasi , Francesco C. De Vecchi , Massimiliano Gubinelli

We use the theory of regularity structures to develop an It\^o formula for $u$, the solution of the one dimensional stochastic heat equation driven by space-time white noise with periodic boundary conditions. In particular for any smooth…

Probability · Mathematics 2024-03-13 Carlo Bellingeri

We derive an It\^o's-type formula for the one dimensional stochastic heat equation driven by a space-time white noise. The proof is based on elementary properties of the $\mathcal{S}$-transform and on the explicit representation of the…

Probability · Mathematics 2007-05-23 Alberto Lanconelli

In this paper, we investigate a stochastic Hardy-Littlewood-Sobolev inequality. Due to the stochastic nature of the inequality, the relation between the exponents of intgrability is modified. This modification can be understood as a…

Analysis of PDEs · Mathematics 2017-11-21 Romain Duboscq , Anthony Réveillac

We develop a stochastic formulation of cosmology in the early universe, after considering the scatter in the redshift-apparent magnitude diagram in the early epochs as an observational evidence for the non-deterministic evolution of early…

Astrophysics · Physics 2015-06-24 C. Sivakumar , Moncy V. John , K. Babu Joseph

We present an exact analytical solution of the Einstein equations with cosmological constant in a spatially flat Robertson-Walker metric. This is interpreted as an isotropic Lemaitre-type version of the cosmological Friedmann model.…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Ion I. Cotaescu , Dumitru N. Vulcanov

The stochastic theory of relativistic quantum mechanics presented here is modelled on the one that has been proposed previously and that was claimed to be a promising substitute to the orthodox theory in the non-relativistic domain. So it…

Quantum Physics · Physics 2020-06-09 Maurice Godart

In this paper, the hyperbolic Anderson equation generated by a time-dependent Gaussian noise is under investigation in two fronts: The solvability and large-$t$ asymptotics. The investigation leads to a necessary and sufficient condition…

Probability · Mathematics 2025-10-03 Xia Chen

We consider the Langevin equation with multiplicative noise term which depends on time and space. The corresponding Fokker-Planck equation in Stratonovich approach is investigated. Its formal solution is obtained for an arbitrary…

Soft Condensed Matter · Physics 2013-05-29 Kwok Sau Fa