Lorentz and CPT Tests with Charge-to-Mass Ratio Comparisons in Penning Traps

Lorentz and CPT invariances are fundamental symmetries of both general relativity and the Standard Model of particle physics. However, tiny violations of these symmetries are possible in an underlying theory unifying gravity with quantum physics, such as strings. This talk will focus on the theoretical and experimental prospects for Lorentz and CPT violation in Penning-trap experiments. The theory of Lorentz violation in quantum electrodynamics will be presented, and experimental observables related to charge-to-mass ratio comparisons will be established for Penning-trap experiments involving confined particles and antiparticles. New constraints on coefficients for Lorentz violation using existing data from ATRAP and BASE experiments will be presented.