A great surprise for physicists: theoretical backgrounds of the quantum electrodynamics may undergo fantastic revision

The proton shrinks in size

Published online 7 July 2010 Nature doi:10.1038/news.2010.337v
http://www.nature.com/news/2010/100707/full/news.2010.337.html

Tiny change in radius has huge implications.

by Geoff Brumfiel

The proton seems to be 0.00000000000003 millimetres smaller than researchers previously thought, according to work published in today's issue of Nature (Pohl, R. et al. Nature 466, 213-217 (2010)).

The difference is so infinitesimal that it might defy belief that anyone, even physicists, would care. But the new measurements could mean that there is a gap in existing theories of quantum mechanics. "It's a very serious discrepancy," says Ingo Sick, a physicist at the University of Basel in Switzerland, who has tried to reconcile the finding with four decades of previous measurements. "There is really something seriously wrong someplace."