Introduction to effective field theories. 1. Heisenberg-Euler effective theory, decoupling of heavy flavours

TL;DR

This paper introduces effective field theories, focusing on the decoupling of heavy particles in quantum electrodynamics and quantum chromodynamics, providing foundational insights into their theoretical framework.

Contribution

It presents an introductory overview of effective field theories with specific emphasis on heavy-particle decoupling in QED and QCD, a topic not extensively covered in prior literature.

Findings

Heavy leptons decouple in QED.

Heavy quarks decouple in QCD.

Foundational understanding of effective field theories.

Abstract

This is the first part of lectures about effective field theories. Decoupling of heavy-particle loops is considered (heavy leptons in QED, heavy quarks in QCD).