Theoretical Analysis of CPT and Lorentz Tests in Penning Traps

Abstract

The CPT theorem has been tested to very high precision in a variety of experiments involving particles and antiparticles confined within Penning traps. These tests include comparisons of anomalous magnetic moments and charge-to-mass ratios of electrons and positrons, protons and antiprotons, and hydrogen ions and antiprotons. We present a theoretical analysis of possible signals for CPT and Lorentz violation in these systems. We use the framework of Colladay and Kostelecký, which consists of a general extension of the $SU(3) \times SU(2) \times U(1)$ standard model including possible CPT and Lorentz violations arising from spontaneous symmetry breaking at a fundamental level, such as in string theory. We work in the context of an extension of quantum electrodynamics to examine CPT and Lorentz tests in Penning traps. Our analysis permits a detailed study of the effectiveness of experimental tests of CPT and Lorentz symmetry performed in Penning traps. We describe possible signals that might appear in principle, and estimate bounds on CPT and Lorentz violation attainable in present and future experiments.