Helicity is the only integral invariant of volume-preserving transformations

Alberto Enciso1, Daniel Peralta-Salas1, Francisco Torres de Lizaur1

  • 1Instituto de Ciencias Matemáticas, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain aenciso@icmat.es dperalta@icmat.es fj.torres@icmat.es.

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