Gravity seminar - Matthew Browning Seminar

 

All stars possess magnetism somewhere in their interiors. In most cases the magnetic fields are built by the action of a magnetic dynamo, a process that converts kinetic energy to magnetic, but a comprehensive theoretical understanding of this process has remained elusive. Here, I will describe some recent results from large-scale simulations of stellar and planetary dynamos, which have helped reveal how orderly fields might be generated amidst the turbulent convection in these objects. I will also discuss claims that particularly strong magnetic fields may affect the structure and radii of low-mass stars; in particular, I will argue that the extreme field strengths needed in some of these models are ruled out by the complementary constraints of buoyancy and Ohmic dissipation. Finally, I will briefly note some possible consequences of extraordinarily dissipative convection for the structure of low-mass stars.