Stochastic PDEs and weakly interacting particle systems

<p>We study two problems relating to weakly interacting particle systems in the presence of exogenous noise. Part I presents a pathwise regularisation by noise result for McKean–Vlasov equations with singular interaction kernels. Using ideas from the theory of averaged fields and non-linear Yo...

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Main Author: Mayorcas, A
Other Authors: Hambly, B
Format: Thesis
Language:English
Published: 2020
Subjects:
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author Mayorcas, A
author2 Hambly, B
author_facet Hambly, B
Mayorcas, A
author_sort Mayorcas, A
collection OXFORD
description <p>We study two problems relating to weakly interacting particle systems in the presence of exogenous noise. Part I presents a pathwise regularisation by noise result for McKean–Vlasov equations with singular interaction kernels. Using ideas from the theory of averaged fields and non-linear Young integrals we obtain well-posedness of the McKean–Vlasov systems, particle approximations and mean field convergence.</p> <p>In Part II we study a family of semi-linear, convection-diffusion SPDEs that are closely related to PDEs coming from the theory of collision-less kinetics. We study these equations in the presence of additive spacetime white noise. In one dimension we show global well-posedness and exponential ergodicity for an equation with a cubic non-linearity and repulsive sign choice. In two dimensions we show local well-posedness for a renormalised equation.</p>
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spelling oxford-uuid:6cb19c41-0598-4b23-bcb6-bf91ce44c7272022-03-26T19:12:41ZStochastic PDEs and weakly interacting particle systemsThesishttp://purl.org/coar/resource_type/c_db06uuid:6cb19c41-0598-4b23-bcb6-bf91ce44c727Stochastic partial differential equationsMathematicsStochastic analysisEnglishHyrax Deposit2020Mayorcas, AHambly, BChevyrev, IWeber, HQian, Z<p>We study two problems relating to weakly interacting particle systems in the presence of exogenous noise. Part I presents a pathwise regularisation by noise result for McKean–Vlasov equations with singular interaction kernels. Using ideas from the theory of averaged fields and non-linear Young integrals we obtain well-posedness of the McKean–Vlasov systems, particle approximations and mean field convergence.</p> <p>In Part II we study a family of semi-linear, convection-diffusion SPDEs that are closely related to PDEs coming from the theory of collision-less kinetics. We study these equations in the presence of additive spacetime white noise. In one dimension we show global well-posedness and exponential ergodicity for an equation with a cubic non-linearity and repulsive sign choice. In two dimensions we show local well-posedness for a renormalised equation.</p>
spellingShingle Stochastic partial differential equations
Mathematics
Stochastic analysis
Mayorcas, A
Stochastic PDEs and weakly interacting particle systems
title Stochastic PDEs and weakly interacting particle systems
title_full Stochastic PDEs and weakly interacting particle systems
title_fullStr Stochastic PDEs and weakly interacting particle systems
title_full_unstemmed Stochastic PDEs and weakly interacting particle systems
title_short Stochastic PDEs and weakly interacting particle systems
title_sort stochastic pdes and weakly interacting particle systems
topic Stochastic partial differential equations
Mathematics
Stochastic analysis
work_keys_str_mv AT mayorcasa stochasticpdesandweaklyinteractingparticlesystems