In the paper by D. Burago, S. Ivanov and A. Novikov, “A survival guide for feeble fish”, it has been shown that a fish with limited velocity can reach any point in the (possibly unbounded)ocean provided that the fluid velocity field is incompressible, bounded and has vanishing mean drift. This result extends some known global controllability theorems though being substantially nonconstructive. We give a fish a different recipe of how to survive in a turbulent ocean, and show its relationship to structural stability of dynamical systems by providing a constructive way to change slightly the velocity field to produce conservative (in the sense of not having wandering sets of positive measure)dynamics. In particular, this leads to the extension of C. Pugh's closing lemma to incompressible vector fields over unbounded domains. The results are based on an extension of the Poincaré recurrence theorem to some σ-finite measures and on specially constructed Newtonian potentials.

Original languageEnglish
Pages (from-to)3442-3474
Number of pages33
JournalJournal of Differential Equations
Volume267
Issue number6
DOIs
StatePublished - 5 Sep 2019

    Research areas

  • Global controllability, Pugh closing lemma, Structural stability, CONTINUITY EQUATIONS

    Scopus subject areas

  • Analysis
  • Applied Mathematics

ID: 41279860