0000000000210904

AUTHOR

James-michael Leahy

0000-0003-4771-4476

showing 3 related works from this author

Solution properties of the incompressible Euler system with rough path advection

2021

The present paper aims to establish the local well-posedness of Euler's fluid equations on geometric rough paths. In particular, we consider the Euler equations for the incompressible flow of an ideal fluid whose Lagrangian transport velocity possesses an additional rough-in-time, divergence-free vector field. In recent work, we have demonstrated that this system can be derived from Clebsch and Hamilton-Pontryagin variational principles that possess a perturbative geometric rough path Lie-advection constraint. In this paper, we prove the local well-posedness of the system in $L^2$-Sobolev spaces $H^m$ with integer regularity $m\ge \lfloor d/2\rfloor+2$ and establish a Beale-Kato-Majda (BKM)…

Physics::Fluid DynamicsMathematics - Analysis of PDEsProbability (math.PR)FOS: MathematicsMathematics::Analysis of PDEs60L20 60L50 60H15 76B03 35Q31VDP::Matematikk og Naturvitenskap: 400::Matematikk: 410AnalysisMathematics - ProbabilityAnalysis of PDEs (math.AP)
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On a rough perturbation of the Navier-Stokes system and its vorticity formulation

2019

We introduce a rough perturbation of the Navier-Stokes system and justify its physical relevance from balance of momentum and conservation of circulation in the inviscid limit. We present a framework for a well-posedness analysis of the system. In particular, we define an intrinsic notion of solution based on ideas from the rough path theory and study the system in an equivalent vorticity formulation. In two space dimensions, we prove that well-posedness and enstrophy balance holds. Moreover, we derive rough path continuity of the equation, which yields a Wong-Zakai result for Brownian driving paths, and show that for a large class of driving signals, the system generates a continuous rando…

Statistics and ProbabilityRough pathMathematical analysisProbability (math.PR)VorticityEnstrophyMomentumPhysics::Fluid DynamicsMathematics - Analysis of PDEsInviscid flowFOS: MathematicsLimit (mathematics)Statistics Probability and UncertaintyRandom dynamical systemBrownian motionMathematics - ProbabilityMathematicsAnalysis of PDEs (math.AP)
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Variational principles for fluid dynamics on rough paths

2022

In this paper, we introduce a new framework for parametrization schemes (PS) in GFD. Using the theory of controlled rough paths, we derive a class of rough geophysical fluid dynamics (RGFD) models as critical points of rough action functionals. These RGFD models characterize Lagrangian trajectories in fluid dynamics as geometric rough paths (GRP) on the manifold of diffeomorphic maps. Three constrained variational approaches are formulated for the derivation of these models. The first is the Clebsch formulation, in which the constraints are imposed as rough advection laws. The second is the Hamilton-Pontryagin formulation, in which the constraints are imposed as right-invariant rough vector…

Mathematics - Analysis of PDEsGeneral MathematicsProbability (math.PR)Fluid Dynamics (physics.flu-dyn)FOS: MathematicsFOS: Physical sciencesVDP::Matematikk og Naturvitenskap: 400Dynamical Systems (math.DS)Physics - Fluid DynamicsMathematics - Dynamical SystemsMathematics - ProbabilityAnalysis of PDEs (math.AP)
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