Charge conjugation from space-time inversion in QED: discrete and continuous groups

TL;DR

This paper explores how the CPT symmetry groups in QED arise from space-time inversion symmetries and their relation to continuous Lorentz and Poincaré groups, revealing underlying group-theoretic structures.

Contribution

It demonstrates the natural emergence of CPT groups from Lorentz subgroup structures and establishes connections with continuous symmetry groups in QED.

Findings

CPT groups derive from PT and P (or T) subgroups of the Lorentz group.

Relationships between discrete CPT groups and continuous Lorentz and Poincaré groups are established.

The study links discrete space-time symmetries with continuous group structures in quantum electrodynamics.

Abstract

We show that the CPT groups of QED emerge naturally from the PT and P (or T) subgroups of the Lorentz group. We also find relationships between these discrete groups and continuous groups, like the connected Lorentz and Poincar\'e groups and their universal coverings.