Proton Mass Shift in Muonic Hydrogen Atom

TL;DR

This paper proposes that the proton mass varies depending on the bound state in muonic or electronic hydrogen due to magnetic field effects altering the chiral condensate, potentially explaining the proton radius puzzle.

Contribution

It introduces a novel mechanism linking bound state magnetic fields to proton mass shifts, offering a new perspective on proton structure in hydrogen atoms.

Findings

Proton mass shift in muonic hydrogen can be around 0.1 meV.

The effect may resolve the proton radius puzzle.

Magnetic field effects inside the proton influence chiral condensate.

Abstract

We show that the value of the proton mass depends on each bound state of muonic or electronic hydrogen atom. The charged particle bound to the proton produces magnetic field inside the proton. This makes a change to the amount of chiral condensate inside the proton. The change gives rise to the shift in the value of the proton mass. Numerically, the shift in the $2S$ state of the muonic hydrogen atom can be of the order of $0.1$ meV. The effect may solve the puzzle of the proton radius.