Abstract

Efforts to model the formation of extrasolar planetary systems have faced an obstacle in the poorly known properties and evolutionary histories of protoplanetary disks. I will review work to model protoplantary disks from first principles, and describe how ALMA observations may be able to directly test theory in the outer disk. Our simulations suggest that disk turbulence and accretion in young stars retains a critical memory of the magnetic fields present when the star formed. I will discuss how the turbulent environment of planet formation affects major phases of planet formation and migration, and argue that a final stage of violent planetary dynamics largely determines what we observe in extrasolar planetary systems.