After a decade of serious disagreement in Physics about the size of a Proton, the answer is finally clear.
There were different ways used to measure the size of a proton. One using electrons, another using muons.
However, both gave results that disagreed by about 5 %. This 5 % disagreement was a big deal since each measurement claimed to be accurate to better than 1 %.
No one was sure whether the discrepancy was because of some genuinely weird physics, or because one of these measurements was incorrect.
However, a careful high-precision measurement using hydrogen atoms that Branco Weiss Fellow Amar Vutha had initiated as a postdoc has found the true result
Amar Vutha worked on the same for 8 years. The study shows that the proton’s size is 0.84 femtometers, whether measured using electrons or using muons.