The Mass of a Spin Vortex, in a Bose Einstein Condensate

Ferromagnetic condensates can have both spin-current and charge-current vortices. A moving charge-vortex experiences the Magnus force, perpendicular to its motion, when it moves. This effective ``magnetic field" is so strong that it dominates the inertial term in Newton's law; therefore it is not possible to set a charge-vortex moving at an arbitrary speed relative to the condensate. As we will show, a spin-vortex \emph{can} move ``inertially" through a condensate and resists acceleration with a mass.