SC317, National Chiao Tung University Science Building III
(國立交通大學科學三館 SC317)
Schrödinger’s Smoke: Fluid Simulations with Hopf Fibration
Albert Chern (California Institute of Technology)
Abstract
Simulation of nearly inviscid incompressible fluids has been a challenging numerical task. We describe a new approach for simulation of incompressible fluids by representing the fluid state with a wavefunction evolving under the Schrödinger equation subject to incompressibility constraints. The underlying dynamics satisfies the Euler equation modified with a Landau-Lifshitz force. The latter ensures that dynamics due to thin vortical structures are faithfully reproduced. This enables robust simulation of intricate phenomena such as vortical wakes and interacting vortex filaments, even on modestly sized grids. The numerical algorithms for time evolution are exceedingly simple. In the talk I will also discuss the underlying theory which reveals fascinating relations between the Clebsch variables in classical fluids, spins in quantum mechanics, Landau-Lifshitz theory of ferromagnetic material, and the geometry of the 3-sphere.