An index for closed orbits in Beltrami fields
Joint work with Robert Ghrist. 
Phys. D  159 (2001), no. 3-4, 180-189.
 
We consider the class of Beltrami fields (eigenfields of the  curl operator) on three-dimensional Riemannian solid tori: such  vector fields arise as steady incompressible inviscid fluids  and plasmas. Using techniques from contact geometry, we construct  an integer-valued index for detecting closed orbits in the flow which are topologically inessential (they have winding number zero with respect to the solid torus). This index is independent of the Riemannian structure, and is  computable entirely from a $C^1$ approximation to the  vector field on any meridional disc of the solid torus. 
 You may download a pdf version of this paper.
 You may download the published version of this paper. (Access may be restricted.) 
 You may download the version of this paper at the arxiv. 
 This paper has been reviewed in math reviews. (Access may be restricted.)
 
  Return to my home page.
           
            |   |