Magnetohydrodynamics: Modeling and Equations

This lecture introduces the physics of plasmas, focusing on magnetohydrodynamics (MHD). The instructor covers the two-fluid model, MHD equations, conservation of energy, Alfvén's theorem, solar wind, Parker spiral, magnetic reconnection, dynamos, and MHD waves. The lecture discusses the challenges of modeling plasmas, including the impossibility of Maxwell's equations. Various scales, from particle number to spatial dimensions, are explored, with a focus on ITER. The lecture also delves into the equations of state, continuity, and closure in the two-fluid model, emphasizing the conservation of mass. The Alfven theorem, magnetic field dynamics, and collisional effects are discussed in the context of MHD.