Transport and Equilibration in Hot Quantum Chromodynamics Abstract

Heavy ion collisions are a laboratory to explore the strong interactions - QCD - under extremes of temperature and density. I will give a theorist's-eye view of heavy ion collisions and the role of nonequilibrium physics. I will discuss the role of viscous hydrodynamics, and the attempts and obstacles to first-principles calculations of the shear viscosity and other transport coefficients, including a novel approach to tunneling phenomena.