Muonic Atom Lamb Shifts via Simple Means and the Proton Radius Problem

A new simple method for understanding and calculating Lamb shifts to better than 1% is introduced and applied to muonic hydrogen and muonic deuterium systems. The hydrogen and deuterium Lamb shifts are due to an intrinsic fuzziness for the bound electron and muon probing the electric field near the proton, associated with their interaction with the vacuum, of 74 fm and 0.36 fm respectively. The smallness of the muon fuzziness suggests that the associated Lamb shifts need to be calculated including some aspects of the internal degrees of freedom of the proton. If the charge of the proton is assumed to be contained within a quasi-free p ⁺ for half of the time, then the calculated mp and md Lamb shifts are consistent with experiment without a need for a change in the proton radius.