Basic Physics of QED

Basic physics of quantum electrodynamics (QED) is reviewed in comparison with quantum mechanics. Under external source of electromagnetic fields, charged particles can be accelerated by the Lorentz force. The Lorentz force is compensated by tension at any point of the Minkowski space-time. The tension is given by the divergence of internal self-stress tensor. The antisymmetric component of the stress tensor leads to spin torque and drives time evolution of electron spin. This is called the quantum electron spin vorticity principle. The spin torque can be compensated by a force called zeta force.