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Brownian motions on a metric graph are defined, their Feller property is proved, and their generators are characterized. This yields a version of Feller's theorem for metric graphs.

Probability · Mathematics 2010-12-07 Vadim Kostrykin , Jürgen Potthoff , Robert Schrader

This article is a mathematical analysis of the Open Quantum Brownian Motion. This object was introduced by Bernard, Bauer, Benoist and Tilloy as the limit of a family of Open Quantum Random Walks on the discrete line. We prove the…

Mathematical Physics · Physics 2019-10-04 Andreys Simon

The indefinite integral of the homogenized Ornstein-Uhlenbeck process is a well-known model for physical Brownian motion, modelling the behaviour of an object subject to random impulses [L. S. Ornstein, G. E. Uhlenbeck: On the theory of…

Probability · Mathematics 2013-02-12 Peter Friz , Paul Gassiat , Terry Lyons

We consider a family of free multiplicative Brownian motions $b_{s,\tau}$ parametrized by a real variance parameter $s$ and a complex covariance parameter $\tau.$ We compute the Brown measure $\mu_{s,\tau}$ of $ub_{s,\tau },$ where $u$ is a…

Probability · Mathematics 2023-08-04 Brian C. Hall , Ching-Wei Ho

The signature is a collection of iterated integrals describing the "shape" of a path. It appears naturally in the Taylor expansions of controlled differential equations and, as a consequence, is arguably the central object within rough path…

Numerical Analysis · Mathematics 2025-10-31 James Foster

We describe a formalization of forcing using Boolean-valued models in the Lean 3 theorem prover, including the fundamental theorem of forcing and a deep embedding of first-order logic with a Boolean-valued soundness theorem. As an…

Logic in Computer Science · Computer Science 2019-04-25 Jesse Michael Han , Floris van Doorn

We lay the theoretical and mathematical foundations of the square root of Browniam motion and we prove the existence of such a process. In doing so, we consider Brownian motion on quantized noncommutative Riemannian manifolds and show how a…

Quantum Physics · Physics 2021-05-13 Marco Frasca , Alfonso Farina , Moawia Alghalith

We present the formalization of Doob's martingale convergence theorems in the mathlib library for the Lean theorem prover. These theorems give conditions under which (sub)martingales converge, almost everywhere or in $L^1$. In order to…

Logic in Computer Science · Computer Science 2022-12-13 Kexing Ying , Rémy Degenne

The real trees form a class of metric spaces that extends the class of trees with edge lengths by allowing behavior such as infinite total edge length and vertices with infinite branching degree. We use Dirichlet form methods to construct…

Probability · Mathematics 2011-10-12 Siva Athreya , Michael Eckhoff , Anita Winter

In this paper, we will present a strong (or pathwise) approximation of standard Brownian motion by a class of orthogonal polynomials. The coefficients that are obtained from the expansion of Brownian motion in this polynomial basis are…

Numerical Analysis · Mathematics 2020-05-21 James Foster , Terry Lyons , Harald Oberhauser

Brownian motion of a particle with an arbitrary shape is investigated theoretically. Analytical expressions for the time-dependent cross-correlations of the Brownian translational and rotational displacements are derived from the…

Statistical Mechanics · Physics 2015-02-13 Bodan Cichocki , Maria L. Ekiel-Jezewska , Eligiusz Wajnryb

The purpose of this work is to construct a {\it Brownian motion} with values in simplicial complexes with piecewise differential structure. In order to state and prove the existence of such Brownian motion, we define a family of continuous…

Probability · Mathematics 2007-05-23 Taoufik Bouziane

In this paper, we show an approximation in law of the complex Brownian motion by processes constructed from a stochastic process with independent increments. We give sufficient conditions for the characteristic function of the process with…

Probability · Mathematics 2013-08-28 Xavier Bardina , Carles Rovira

The signature of a $d$-dimensional Brownian motion is a sequence of iterated Stratonovich integrals along the Brownian paths, an object taking values in the tensor algebra over $\RR^{d}$. In this note, we derive the exact rate of…

Probability · Mathematics 2012-11-26 Hao Ni , Weijun Xu

In this monograph, we construct and study a sigma-finite measure on continuous functions from R_+ to R, strongly related to many probability measures obtained by penalisation of Brownian motion, i.e. as limits of probabilities which are…

Probability · Mathematics 2009-05-15 Joseph Najnudel , Bernard Roynette , Marc Yor

This article summarizes the various ways one may use to construct the Skew Brownian motion, and shows their connections. Recent applications of this process in modelling and numerical simulation motivates this survey. This article ends with…

Probability · Mathematics 2007-05-23 Antoine Lejay

Assume that $X$ is a continuous square integrable process with zero mean, defined on some probability space $(\Omega,\mathrm {F},\mathrm {P})$. The classical characterization due to P. L\'{e}vy says that $X$ is a Brownian motion if and only…

Probability · Mathematics 2011-03-15 Yuliya Mishura , Esko Valkeila

In this article we describe the formalisation of the Bruhat-Tits tree - an important tool in modern number theory - in the Lean Theorem Prover. Motivated by the goal of connecting to ongoing research, we apply our formalisation to verify a…

Number Theory · Mathematics 2026-04-22 Judith Ludwig , Christian Merten

In this article we explore the phenomena of nonequilibrium stochastic process starting from the phenomenological Brownian motion. The essential points are described in terms of Einstein's theory of Brownian motion and then the theory…

Physics Education · Physics 2007-05-23 Deb Shankar Ray

We derive explicit forms of Markovian transition probability densities for the velocity space, phase-space and the Smoluchowski configuration-space Brownian motion of a charged particle in a constant magnetic field. By invoking a…

Statistical Mechanics · Physics 2009-10-31 R. Czopnik , P. Garbaczewski