Effective Field Theory

Abstract

These lectures provide an introduction to the basic ideas and methods of Effective Field Theory, and a description of a few interesting phenomenological applications in particle physics. The main conceptual foundations are discussed in sections 2 and 3, which cover the momentum expansion and the most important issues associated with the renormalization process. Section 4 presents an overview of Chiral Perturbation Theory, the low-energy realization of Quantum Chromodynamics in the light quark sector. The Chiral Perturbation Theory framework is applied to weak transitions in section 5, where the physics of non-leptonic kaon decays is analyzed. The so-called Heavy Quark Effective Theory is briefly discussed in section 6. The electroweak chiral Effective Field Theory is described in section 7, which contains a brief overview of the effective Lagrangian associated with the spontaneous electroweak symmetry breaking. Some summarizing comments are finally given in section 8.