A Geometric Heat-Flow Theory of Lagrangian Coherent Structures

@article{Karrasch2020AGH,
  title={A Geometric Heat-Flow Theory of Lagrangian Coherent Structures},
  author={Daniel Karrasch and Johannes Keller},
  journal={Journal of Nonlinear Science},
  year={2020},
  volume={30},
  pages={1849-1888}
}
We consider Lagrangian coherent structures (LCSs) as the boundaries of material subsets whose advective evolution is metastable under weak diffusion. For their detection, we first transform the Eulerian advection–diffusion equation to Lagrangian coordinates, in which it takes the form of a time-dependent diffusion or heat equation. By this coordinate transformation, the reversible effects of advection are separated from the irreversible joint effects of advection and diffusion. In this… 
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