English
Related papers

Related papers: Random walk diffusion simulations in semi-permeabl…

200 papers

We introduce a model for translational molecular motors to demonstrate that a multivalent catalytic walker with flexible, uncoordinated legs can transform the free energy of surface-bound substrate sites into mechanical work and undergo…

Biological Physics · Physics 2014-11-18 Mark J. Olah , Darko Stefanovic

We introduce a new self-interacting random walk on the integers in a dynamic random environment and show that it converges to a pure diffusion in the scaling limit. We also find a lower bound on the diffusion coefficient in some special…

Probability · Mathematics 2007-05-23 Majid Hosseini , Krishnamurthi Ravishankar

Self-activation coupled to a transport mechanism results in traveling waves that describe polymerization reactions, forest fires, tumor growth, and even the spread of epidemics. Diffusion is a simple and commonly used model of particle…

Statistical Mechanics · Physics 2020-07-06 Keisuke Ishihara , Ashish B. George , Ryan Cornelius , Kirill S. Korolev

We develop a time domain random walk approach for conservative solute transport in heterogeneous media where medium properties vary over a distribution of length scales. The spatial transition lengths are equal to the heterogeneity length…

Fluid Dynamics · Physics 2018-09-05 Tomás Aquino , Marco Dentz

Nonergodicity observed in single-particle tracking experiments is usually modeled by transient trapping rather than spatial disorder. We introduce models of a particle diffusing in a medium consisting of regions with random sizes and random…

Soft Condensed Matter · Physics 2014-09-23 P. Massignan , C. Manzo , J. A. Torreno-Pina , M. F. García-Parajo , M. Lewenstein , G. J. Lapeyre

Active walker models have proved to be extremely effective in understanding the evolution of a large class of systems in biology like ant trail formation and pedestrian trails. We propose a simple model of a random walker which modifies its…

Biological Physics · Physics 2023-01-18 Subhashree Subhrasmita Khuntia , Abhishek Chaudhuri , Debasish Chaudhuri

Random walks with a general, nonlinear barrier have found recent applications ranging from reionization topology to refinements in the excursion set theory of halos. Here, we derive the first-crossing distribution of random walks with a…

Astrophysics · Physics 2009-11-13 Jun Zhang , Lam Hui

Medical image segmentation is a challenging task, made more difficult by many datasets' limited size and annotations. Denoising diffusion probabilistic models (DDPM) have recently shown promise in modelling the distribution of natural…

Computer Vision and Pattern Recognition · Computer Science 2023-11-14 Margherita Rosnati , Melanie Roschewitz , Ben Glocker

We show that particle transport in a uniform, quantum multi-baker map, is generically ballistic in the long time limit, for any fixed value of Planck's constant. However, for fixed times, the semi-classical limit leads to diffusion. Random…

Quantum Physics · Physics 2009-11-07 Daniel K. Wojcik , J. R. Dorfman

We consider a classic two-state switching diffusion model from a single-particle tracking perspective. The mean and the variance of the time-averaged mean square displacement (TAMSD) are computed exactly. When the measurement time (i.e.,…

Statistical Mechanics · Physics 2019-11-05 Denis S. Grebenkov

Modelling the propagation of a pulse in a dense {\em milieu} poses fundamental challenges at the theoretical and applied levels. To this aim, in this paper we generalize the telegraph equation to non-ideal conditions by extending the…

Statistical Mechanics · Physics 2015-06-16 Marta Galanti , Duccio Fanelli , Francesco Piazza

We study an ensemble of random walkers carrying internal noisy phase oscillators which are synchronized among the walkers by local interactions. Due to individual mobility, the interaction partners of every walker change randomly, hereby…

Statistical Mechanics · Physics 2016-05-04 Robert Großmann , Fernando Peruani , Markus Bär

A theoretical calculation is presented to describe the confined motion of transmembrane molecules in cell membranes. The study is analytic, based on Master equations for the probability of the molecules moving as random walkers, and leads…

Biological Physics · Physics 2009-11-13 V. M. Kenkre , L. Giuggioli , Z. Kalay

The diffusion of a particle in a crowded environment typically proceeds through three regimes: for very short times the particle diffuses freely until it collides with an obstacle for the first time, while for very long times diffusion the…

Biological Physics · Physics 2019-10-09 Nguiya P. Neo , Gary W. Slater

We consider conservative cross-diffusion systems for two species where individual motion rates depend linearly on the local density of the other species. We develop duality estimates and obtain stability and approximation results. We first…

Analysis of PDEs · Mathematics 2024-10-30 Vincent Bansaye , Ayman Moussa , Felipe Muñoz-Hernández

We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental role in simulation-based likelihood and Bayesian inference for stochastic differential equations. By a novel application of classical coupling…

Statistics Theory · Mathematics 2014-06-02 Mogens Bladt , Samuel Finch , Michael Sørensen

We propose random walks on suitably defined graphs as a framework for finescale modeling of particle motion in an obstructed environment where the particle may have interactions with the obstructions and the mean path length of the particle…

Probability · Mathematics 2019-10-25 Preston Donovan , Muruhan Rathinam

Local diffusion coefficients in disordered systems such as spin glass systems and living cells are highly heterogeneous and may change over time. Such a time-dependent and spatially heterogeneous environment results in irreproducibility of…

Statistical Mechanics · Physics 2016-12-21 Takuma Akimoto , Eiji Yamamoto

We examine diffusion-limited aggregation for a one-dimensional random walk with long jumps. We achieve upper and lower bounds on the growth rate of the aggregate as a function of the number of moments a single step of the walk has. In this…

Probability · Mathematics 2013-06-20 Gideon Amir , Omer Angel , Gady Kozma

Quantum walks are known to propagate quadratically faster than their classical counterparts and are used to model dynamics in various quantum systems. The spread of the quantum walk in position space shows anomalous diffusion behavior. By…

Quantum Physics · Physics 2022-05-24 Abhaya S. Hegde , C. M. Chandrashekar