English
Related papers

Related papers: On the causality of real-valued semigroups and dif…

200 papers

In this paper we introduce a new approach to the diffusive limit of the weakly random Schrodinger equation, first studied by L. Erdos, M. Salmhofer, and H.T. Yau. Our approach is based on a wavepacket decomposition of the evolution…

Mathematical Physics · Physics 2024-12-11 Felipe Hernández

We numerically address the stability analysis of linear age-structured population models with nonlocal diffusion, which arise naturally in describing dynamics of infectious diseases. Compared to Laplace diffusion, models with nonlocal…

Numerical Analysis · Mathematics 2024-03-13 Dimitri Breda , Simone De Reggi , Rossana Vermiglio

Diffusion models, which convert noise into new data instances by learning to reverse a Markov diffusion process, have become a cornerstone in contemporary generative modeling. While their practical power has now been widely recognized, the…

Machine Learning · Statistics 2024-03-08 Gen Li , Yuting Wei , Yuxin Chen , Yuejie Chi

The dynamics of spin at finite temperature in the spin-1/2 Heisenberg chain was found to be superdiffusive in numerous recent numerical and experimental studies. Theoretical approaches to this problem have emphasized the role of nonabelian…

Statistical Mechanics · Physics 2022-06-20 Pieter W. Claeys , Austen Lamacraft , Jonah Herzog-Arbeitman

Diffusion model-based approaches have shown promise in data-driven planning, but there are no safety guarantees, thus making it hard to be applied for safety-critical applications. To address these challenges, we propose a new method,…

Machine Learning · Computer Science 2023-06-02 Wei Xiao , Tsun-Hsuan Wang , Chuang Gan , Daniela Rus

We report on recent progress in the study of nonlinear diffusion equations involving nonlocal, long-range diffusion effects. Our main concern is the so-called fractional porous medium equation, $\partial_t u +(-\Delta)^{s}(u^m)=0$, and some…

Analysis of PDEs · Mathematics 2014-01-16 Juan Luis Vázquez

We develop a heavy traffic diffusion limit theorem under nonstandard spatial scaling for the queue length process in a single server queue employing shortest remaining processing time (SRPT). For processing time distributions with unbounded…

Probability · Mathematics 2015-10-29 Amber L. Puha

Typically, aggregation-diffusion is modeled by parabolic equations that combine linear or nonlinear diffusion with a Fokker-Planck convection term. Under very general suitable assumptions, we prove that radial solutions of the evolution…

Analysis of PDEs · Mathematics 2021-12-15 Jose A. Carrillo , David Gómez-Castro , Juan Luis Vázquez

We discuss nonconforming virtual element method for convection dominated (diffusive coefficient is very small compared to convective coefficient and reac- tion coefficient ) convection-diffusion-reaction equation using L^2 projection…

Numerical Analysis · Mathematics 2016-01-07 Dibyendu Adak , E. Natarajan

We prove that weakly continuous solutions to martingale problems admit a canonical regular conditional probability distribution. This allows for the construction of time consistent convex dynamic procedures in a non dominated setting.…

Probability · Mathematics 2012-10-09 Jocelyne Bion-Nadal

We provide a stochastic fractional diffusion equation description of energy transport through a finite one-dimensional chain of harmonic oscillators with stochastic momentum exchange and connected to Langevian type heat baths at the…

Statistical Mechanics · Physics 2019-05-22 Aritra Kundu , Cédric Bernardin , Keji Saito , Anupam Kundu , Abhishek Dhar

This paper provides a semiparametric model of estimating states of the volatility defined as the squared diffusion coefficient of a stochastic differential equation. Without assuming any functional form of the volatility function, we…

Statistics Theory · Mathematics 2007-07-18 I. Shoji

We study fast / slow systems driven by a fractional Brownian motion $B$ with Hurst parameter $H\in (\frac 13, 1]$. Surprisingly, the slow dynamic converges on suitable timescales to a limiting Markov process and we describe its generator.…

Probability · Mathematics 2023-03-07 Martin Hairer , Xue-Mei Li

Diffusion models have attracted a lot of attention in recent years. These models view speech generation as a continuous-time process. For efficient training, this process is typically restricted to additive Gaussian noising, which is…

Machine Learning · Computer Science 2025-10-14 Xiaozhou Tan , Minghui Zhao , Anton Ragni

We study a diffusion process with random space-time dependent coefficients. Moreover the diffusion matrix is allowed to degenerate. An invariance principle is proved provided that the diffusion coefficient is controlled by a time…

Probability · Mathematics 2016-08-16 Rémi Rhodes

We consider the problem of statistical inference for the effective dynamics of multiscale diffusion processes with (at least) two widely separated characteristic time scales. More precisely, we seek to determine parameters in the effective…

Statistics Theory · Mathematics 2013-05-30 Sebastian Krumscheid , Grigorios A. Pavliotis , Serafim Kalliadasis

The variability of structure in a finite Markov equivalence class of causally sufficient models represented by directed acyclic graphs has been fully characterized. Without causal sufficiency, an infinite semi-Markov equivalence class of…

Artificial Intelligence · Computer Science 2013-02-01 Benoit Desjardins

We use a semiclassical approach to study out of equilibrium dynamics and transport in quantum systems with massive quasiparticle excitations having internal quantum numbers. In the universal limit of low energy quasiparticles, the system is…

Statistical Mechanics · Physics 2019-03-20 Márton Kormos , Catalin Pascu Moca , Gergely Zaránd

Einstein's explanation of Brownian motion provided one of the cornerstones which underlie the modern approaches to stochastic processes. His approach is based on a random walk picture and is valid for Markovian processes lacking long-term…

Statistical Mechanics · Physics 2009-11-10 I. M. Sokolov , J. Klafter

We study the one-dimensional diffusion process which takes place between two reflecting boundaries and which is acted upon by a time-dependent and spatially-constant force. The assumed force possesses both the harmonically oscillating and…

Other Condensed Matter · Physics 2007-05-23 Evzen Subrt , Petr Chvosta