Isolated steady solutions of the 3D Euler equations.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40117316.
- Also identified by DOI 10.1073/pnas.2414730122 and PMC identifier 11962483.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We show that there exist closed three-dimensional Riemannian manifolds where the incompressible Euler equations exhibit smooth steady solutions that are isolated in the <i>C</i><sup>1</sup>-topology. The proof of this fact combines ideas from dynamical systems, which appear naturally because these isolated states have strongly chaotic dynamics, with techniques from spectral geometry and contact topology, which can be effectively used to analyze the steady Euler equations on carefully chosen Riemannian manifolds. Interestingly, much of this strategy carries over to the Euler equations in Euclidean space, leading to the weaker result that there exist analytic steady solutions on [Formula: see text] such that the only analytic steady Euler flows in a <i>C</i><sup>1</sup>-neighborhood must belong to a certain linear space of dimension six. For comparison, note that in any <i>C</i><sup><i>k</i></sup>-neighborhood of a shear flow, there are infinitely many linearly independent analytic shears.