Main category

Natural Sciences (Mathematics)

Abstract

*Quadratic Helicity in MHD* We discuss the definitions and properties of the helicity $\chi$ and of the quadratic helicities \chi^{[2]} and \chi^{(2)} in MHD. A formula for the practical computation of the quadratic helicity density $\chi^{(2)}$ is presented. We also explain why the examples of geodesic flows by P. Dehornoy determine magnetic fields in a 3D domain $\Omega$ of minimal magnetic energy with a constant helicity density and minimal quadratic helicity: $\chi^{(2)} = \chi^2/Vol(\Omega)$. This is a joint result with Simon Candelaresi and Alexandr Smirnov.

Conference

helicity thinkshop 3

Link this presentation

https://science-media.org/presentation/295