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Diffusion on complex networks is often modeled as a stochastic process. Yet, recent work on strategic diffusion emphasizes the decision power of agents and treats diffusion as a strategic problem. Here we study the computational aspects of…

Computational Complexity · Computer Science 2020-01-31 Marcin Waniek , Khaled Elbassioni , Flavio L. Pinheiro , Cesar A. Hidalgo , Aamena Alshamsi

The diffusion and flow of amorphous materials, such as glasses and granular materials, has resisted a simple microscopic description, analogous to defect theories for crystals. Early models were based on either gas-like inelastic collisions…

Statistical Mechanics · Physics 2007-05-23 Martin Z. Bazant

In networks of nonlinear oscillators, symmetries place hard constraints on the system that can be exploited to predict universal dynamical features and steady-states, providing a rare generic organizing principle for far-from-equilibrium…

Pattern Formation and Solitons · Physics 2021-03-02 Ian Hunter , Michael M. Norton , Bolun Chen , Chris Simonetti , Maria Eleni Moustaka , Jonathan Touboul , Seth Fraden

Diffusion-induced Ramsey narrowing that appears when atoms can leave the interaction region and repeatedly return without lost of coherence is investigated using strong collisions approximation. The effective diffusion equation is obtained…

Quantum Physics · Physics 2008-01-23 Alexander Romanenko , Leonid Yatsenko

This paper studies spatial patterns formed by proximate population migration driven by real wage gradients and other idiosyncratic factors. The model consists of a tractable core-periphery model incorporating a quasi-linear log utility…

Theoretical Economics · Economics 2025-07-23 Kensuke Ohtake

A general system of several ordinary differential equations coupled with a reaction-diffusion equation in a bounded domain with zero-flux boundary condition is studied in the context of pattern formation. These initial-boundary value…

Analysis of PDEs · Mathematics 2021-10-29 Szymon Cygan , Anna Marciniak-Czochra , Grzegorz Karch , Kanako Suzuki

We propose a linear programming (LP) framework for steady-state diffusion and flux optimization on geometric networks. The state variable satisfies a discrete diffusion law on a weighted, oriented graph, where conductances are scaled by…

Optimization and Control · Mathematics 2025-11-06 Harbir Antil , Rainald Löhner , Felipe Pérez

We study the packing fraction of clusters in free-falling streams of spherical and irregularly shaped particles using flash X-ray radiography. The estimated packing fraction of clusters is low enough to correspond to coordination numbers…

Soft Condensed Matter · Physics 2021-03-31 Yuuya Nagaashi , Akiko M. Nakamura , Sunao Hasegawa , Koji Wada

Many approaches to modelling reaction-diffusion systems with anomalous transport rely on deterministic equations and ignore fluctuations arising due to finite particle numbers. Starting from an individual-based model we use a…

Statistical Mechanics · Physics 2019-05-29 Joseph W. Baron , Tobias Galla

Consider a species whose population density solves the steady diffusive logistic equation in a heterogeneous environment modeled with the help of a spatially non constant coefficient standing for a resources distribution in a given box. We…

Analysis of PDEs · Mathematics 2018-07-25 Idriss Mazari , Grégoire Nadin , Yannick Privat

We establish the existence of solutions to a class of non-linear stochastic differential equation of reaction-diffusion type in an infinite-dimensional space, with diffusion corresponding to a given transition kernel. The solution obtained…

Probability · Mathematics 2021-08-10 Conrado da Costa , Bernardo Freitas Paulo da Costa , Daniel Valesin

Reaction-diffusion equations are treated on infinite networks using semigroup methods. To blend high fidelity local analysis with coarse remote modeling, initial data and solutions come from a uniformly closed algebra generated by functions…

Dynamical Systems · Mathematics 2013-09-24 Robert Carlson

Spatio-temporal biochemical signaling in a large class of protein-protein interaction networks is well modeled by a reaction-diffusion system. The global existence of the solution to the reaction-diffusion system is determined by the…

Optimization and Control · Mathematics 2013-08-09 Insoon Yang , Claire J. Tomlin

In this article we present a computational framework for isolating spatial patterns arising in the steady states of reaction-diffusion systems. Such systems have been used to model many different phenomena in areas such as developmental and…

Numerical Analysis · Mathematics 2016-04-20 Laura Murphy , Chandrasekhar Venkataraman , Anotida Madzvamuse

If a collection of identical particles is poured into a container, different shapes will fill to different densities. But what is the shape that fills a container as close as possible to a pre-specified, desired density? We demonstrate a…

Soft Condensed Matter · Physics 2014-03-18 Marc Z. Miskin , Heinrich M. Jaeger

We study diffusion-type equations supported on structures that are randomly varying in time. After settling the issue of well-posedness, we focus on the asymptotic behavior of solutions: our main result gives sufficient conditions for…

Dynamical Systems · Mathematics 2020-04-28 Stefano Bonaccorsi , Francesca Cottini , Delio Mugnolo

Patterns in reaction-diffusion systems often contain two spatial scales; a long scale determined by a typical wavelength or domain size, and a short scale pertaining to front structures separating different domains. Such patterns naturally…

patt-sol · Physics 2009-10-22 Aric Hagberg , Ehud Meron

A direct numerical solution of the radiative transfer equation or any kinetic equation is typically expensive, since the radiative intensity depends on time, space and direction. An expansion in the direction variables yields an equivalent…

Mathematical Physics · Physics 2023-10-10 Benjamin Seibold , Martin Frank

In this paper we consider a wide class of discrete diffusion load balancing algorithms. The problem is defined as follows. We are given an interconnection network and a number of load items, which are arbitrarily distributed among the nodes…

Distributed, Parallel, and Cluster Computing · Computer Science 2014-12-23 Hoda Akbari , Petra Berenbrink , Robert Elsässer , Dominik Kaaser

The ecological invasion problem in which a weaker exotic species invades an ecosystem inhabited by two strongly competing native species is modelled by a three-species competition-diffusion system. It is known that for a certain range of…

Populations and Evolution · Quantitative Biology 2018-11-01 Lorenzo Contento , Masayasu Mimura