Exact Results in Quantum Theory

Precision spectroscopy of simple atomic systems requires increasingly accurate theoretical predictions to match the growing precision of experimental measurements. In this work, a significantly improved theory of the muonic hydrogen hyperfine splitting (HFS) is presented in anticipation of upcoming high-precision measurements. The main achievement is the rigorous calculation of some finite nuclear mass (recoil) corrections of order (Zα)2 EF to the hyperfine splitting in hydrogenic systems with focus on radiative corrections.