If you look at precisely how they solved the second order differential Schrรถdinger equation for the hydrogen atom (the only one with an analytical solution), and see how they derived the equation that precisely links the QUANTUM energy steps to frequency/energy (the photon frequency/energy for when the electron jumps shells; Rydberg equation - THE FULL ONE), AND solve it precisely without making their reduced mass approximation, you get the solution to the proton radius puzzle and much more. Requires iteration on a computer to solve AND it is precise.

**The Surfer, OM-IV**