http://www.nature.com/news/2010/100707/full/news.2010.337.html
What is to say: a proton has a given "size" when measured against an electron, and a slighty different one when against a moun.
http://www.nature.com/news/2010/100707/full/news.2010.337.html
What is to say: a proton has a given "size" when measured against an electron, and a slighty different one when against a moun.