"G.P. Thomson performed experiments on electron scattering ... It has been quipped that J.J. Thomson got the Nobel prize for discovering that electrons are particles, and G.P. Thomson got it for discovering that they aren't."

American Institute of Physics, "A Look Inside the Atom"

Image from:  Diffraction of Cathode Rays. III G. P. Thomson Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, Vol. 125, No. 797 (Sep. 2, 1929), pp. 352-370

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