Physicists are puzzled by a new finding that the radius of the proton radius is smaller than previously believed.Protons are one of the three basic building blocks of matter: protons and neutrons form the atomic nucleus, and the nucleus is surrounded by orbiting electrons. The chemical elements are identified by the number of protons in the nucleus. You may have a clear idea about the size of a baseball, but do you know how big a proton is?
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