Speaker
Krzysztof Pachucki
(Warsaw)
Description
The 2010 measurement of the muonic hydrogen Lamb shift by Pohl and collaborators
has questioned our understanding of hydrogenic systems. A significant disagreement with
theoretical predictions, which can be interpreted as a discrepancy in the proton charge
radius between electronic and muonic measurements has not been resolved till now.
A single muonic measurement stands against dozens of electronic hydrogen and electron-
proton scattering ones and no simple extension of the Standard Model can fix this.
We will argue that the only solution which does not violate the lepton universality
is the underestimated uncertainty of all the electronic measurements and it is
the muonic hydrogen value which is the correct one. As a consequence this hypothesis
will cause a significant changes in fundamental physical constants and I will present all
possible means of verifying the new proton charge radius value.
