Dartmouth Events

Title: "Magnetogenesis Through Convection in Barotropic Fluids"

Abstract: One of the main mechanisms for generating magnetic fields in plasmas is the Biermann battery, which relies on the baroclinicity of the plasma. I will present an alternative mechanism, which instead utilizes non-uniform bulk velocity. This new effect can operate even when the initial conditions contain with no fields or currents, uniform densities and pressures, and a divergence-free bulk velocity. It does not depend on the baroclinicity of the plasma, and is therefore relevant even in barotropic flows. Unlike other magnetogenesis mechanisms, it also does not rely on kinetic effects or shear discontinuities. Instead, our magnetogenesis effect arises from convection terms proportional to the electron mass in the generalized Ohm’s law. The resulting magnetic fields are typically weak, but may still serve as seed fields for dynamo mechanisms.