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20172026
most citedUniqueness for contagious McKean--Vlasov systems in the weak feedback regime

19 citations · 52 across the 21 of their papers we have counts for

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math.PR2026

Probabilistic estimates for a system of noisy integrate-and-fire neurons

Ben Hambly, Aldaïr Petronilia, Christoph Reisinger +1

In this note, we establish various probabilistic estimates for an interacting particle system that describes the evolution of the membrane potentials in a network of excitatory int…

math.PR2026

Volterra clocks and their pure-jump limits: hitting times of curved boundaries

Eduardo Abi Jaber, Elie Attal, Andreas Sojmark

We introduce a class of continuous Volterra processes, called Volterra clocks, and study their singular limit as the memory kernel collapses to a Dirac mass at zero. The dynamics a…

math.PR2026

A free boundary problem for the mean-field limit of diffusing particles with nonlinear boundary reactivity

Eliana Fausti, Andreas Sojmark

Consider a finite system of diffusing particles coupled through a reactive boundary. Each particle is reflected, but may react with the boundary according to a killing mechanism wh…

math.PR2025

A Moving Boundary Problem for Brownian Particles with Singular Forward-Backward Interactions

Philipp Jettkant, Andreas Sojmark

We introduce a system of Brownian particles, each absorbed upon hitting an associated moving boundary. The boundaries are determined by the conditional probabilities of the particl…

math.PR2024

The supercooled Stefan problem with transport noise: weak solutions and blow-up

Sean Ledger, Andreas Sojmark

We derive two weak formulations for the supercooled Stefan problem with transport noise on a half-line: one captures a continuously evolving system, while the other resolves blow-u…

math.PR2024

Functional CLTs for subordinated Lévy models in physics, finance, and econometrics

Andreas Søjmark, Fabrice Wunderlich

We present a simple unifying treatment of a broad class of applications from statistical mechanics, econometrics, mathematical finance, and insurance mathematics, where (possibly s…

math.PR2024

Functional weak convergence of stochastic integrals for moving averages and continuous-time random walks

Andreas Søjmark, Fabrice Wunderlich

There is an extensive theory of weak convergence for moving averages and continuous-time random walks (CTRWs) with respect to Skorokhod's M1 and J1 topologies. Here we address the…

math.PR2023

Weak Convergence of Stochastic Integrals on Skorokhod Space in Skorokhod's J1 and M1 Topologies

Andreas Sojmark, Fabrice Wunderlich

We provide criteria for Itô integration to behave continuously with respect to Skorokhod's J1 and M1 topologies, when the integrands and integrators converge weakly or in probabili…

math.PR2023★ 2 cited

Contagious McKean--Vlasov problems with common noise: from smooth to singular feedback through hitting times

Ben Hambly, Aldaïr Petronilia, Christoph Reisinger +2

We consider a family of McKean--Vlasov equations arising as the large particle limit of a system of interacting particles on the positive half-line with common noise and feedback.…

math.PR2022

An SPDE with Robin-type boundary for a system of elastically killed diffusions on the positive half-line

Ben Hambly, Julian Meier, Andreas Sojmark

We consider a system of particles undergoing correlated diffusion with elastic boundary conditions on the half-line. By taking the large particle limit we establish existence and u…

math.PR2022★ 2 cited

An interacting particle system for the front of an epidemic advancing through a susceptible population

Eliana Fausti, Andreas Sojmark

We introduce an interacting particle system that models the spread of an epidemic in terms of heterogeneous diffusive dynamics, rather than exogenous contact and transmission rates…

math.PR2021

Contagious McKean-Vlasov systems with heterogeneous impact and exposure

Zachary Feinstein, Andreas Sojmark

We introduce a heterogeneous formulation of a contagious McKean-Vlasov system, whose inherent heterogeneity comes from asymmetric interactions with a natural and highly tractable s…

math.PR2018★ 19 cited

Uniqueness for contagious McKean--Vlasov systems in the weak feedback regime

Sean Ledger, Andreas Sojmark

We present a simple uniqueness argument for a collection of McKean-Vlasov problems that have seen recent interest. Our first result shows that, in the weak feedback regime, there i…

math.PR2018

At the Mercy of the Common Noise: Blow-ups in a Conditional McKean--Vlasov Problem

Sean Ledger, Andreas Sojmark

We extend a model of positive feedback and contagion in large mean-field systems, by introducing a common source of noise driven by Brownian motion. Although the driving dynamics a…

math.PR2018★ 10 cited

An SPDE Model for Systemic Risk with Endogenous Contagion

Ben Hambly, Andreas Sojmark

We propose a dynamic mean field model for `systemic risk' in large financial systems, which we derive from a system of interacting diffusions on the positive half-line with an abso…

math.PR2018★ 8 cited

A McKean--Vlasov equation with positive feedback and blow-ups

Ben Hambly, Sean Ledger, Andreas Sojmark

We study a McKean--Vlasov equation arising from a mean-field model of a particle system with positive feedback. As particles hit a barrier they cause the other particles to jump in…

math.PR2017

Functional central limit theorems for rough volatility

Blanka Horvath, Antoine Jacquier, Aitor Muguruza +1

The non-Markovian nature of rough volatility processes makes Monte Carlo methods challenging and it is in fact a major challenge to develop fast and accurate simulation algorithms.…