Effective Field Theory

TL;DR

This paper introduces the fundamental concepts and methods of Effective Field Theory, illustrating their applications in particle physics, including Chiral Perturbation Theory, Heavy Quark Effective Theory, and electroweak EFT.

Contribution

It provides a comprehensive overview of Effective Field Theory frameworks and their phenomenological applications in particle physics, emphasizing conceptual foundations and specific theories.

Findings

Overview of momentum expansion and renormalization issues

Application of Chiral Perturbation Theory to kaon decays

Discussion of Heavy Quark and Electroweak Effective Theories

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.