Decoupling in QED and QCD

TL;DR

This paper explores the decoupling of heavy particles in quantum electrodynamics and quantum chromodynamics, providing detailed calculations up to two loops to clarify the process.

Contribution

It offers a pedagogical analysis of decoupling in QED and QCD, including explicit two-loop calculations for muons in QED.

Findings

Decoupling of heavy flavors can be systematically analyzed in QED and QCD.

Explicit two-loop calculations demonstrate the decoupling process.

The approach clarifies the theoretical framework for heavy flavor decoupling.

Abstract

Decoupling of a heavy flavour in QCD is discussed in a pedagogical way. First we consider a simpler case: decoupling of muons in QED. All calculations are done up to 2 loops.