Physics Commons^™

Evaluating The Effective Action, Br Holstein

Barry R Holstein

The use of effective field theory, in situations wherein the energy-momentum of light particles is much lower than the rest mass of heavy degrees of freedom, has become an important one in contemporary physics. Herein we examine various means by which this effective action can be evaluated, using the effective photon–photon interaction—the Euler–Heisenberg Lagrangian—as a pedagogical example.