General aspects of effective field theories and few-body applications

TL;DR

This paper discusses the principles of effective field theories, focusing on their application to few-body systems in nuclear physics, including nonperturbative interactions and extensions to long-range forces.

Contribution

It provides a comprehensive overview of effective field theory methods applied to few-body physics, highlighting nonperturbative treatment and extensions to long-range interactions.

Findings

Effective field theory effectively describes low-energy nuclear systems.

Nonperturbative treatment is essential for resonant short-range interactions.

Extensions to include long-range forces like photon and pion exchange are feasible.

Abstract

Effective field theory provides a powerful framework to exploit a separation of scales in physical systems. In these lectures, we discuss some general aspects of effective field theories and their application to few-body physics. In particular, we consider an effective field theory for non-relativistic particles with resonant short-range interactions where certain parts of the interaction need to be treated nonperturbatively. As an application, we discuss the so-called pionless effective field theory for low-energy nuclear physics. The extension to include long-range interactions mediated by photon and pion-exchange is also addressed.