In the May issue of Scientific American, a familiar friend makes an appearance: a chart of fundamental particles. These particles–fermions (which include constituents of matter such as electrons and quarks) and bosons (usually carriers of force)–are at the very heart of the Standard Model of particle physics. Visualizing them in table form has become a bit of a tradition here at the magazine, as a way to introduce readers to the cast of characters in articles on the topic, and to provide context for theorized and newly described particles.
Below is a time-ordered series of my favorite particle zoo tables from the Scientific American archive, starting with a comprehensive particle list from 1952, morphing into the discovery-driven Standard Model classifications of the 1970s and beyond. Variation reflects the shifting state of particle physics knowledge over time, different themes addressed by the full articles the tables accompany, and aesthetic trends (influenced by the rendering and print production tools available at the time).
All the particles known as of December, 1951, including fundamental species such as electrons, composite particles, including protons and neutrons (each made of quarks), and theorized particles such as the graviton (which still has not been confirmed): From “The Multiplicity of Particles” by Robert E. Marshak, in Scientific American, January, 1952. Graphic by Sara Love
Thirty Particles of 1957: From “Strongly Interacting Particles” by Geoffrey F. Chew, Murray Gell-Mann and Arthur H. Rosenfeld, in Scientific American, February 1964. Graphic by Joan Starwood
Subatomic particles (top) and quark hypothesis (bottom): From “Electron-Positron Annihilation and the New Particles” by Sidney D. Drell, in Scientific American, June 1975. Graphics by George V. Kelvin
Standard model of elementary-particle interactions: From “Gauge Theories of the Forces Between Elementary Particles” by Gerard’t Hooft, in Scientific American, June 1980. Graphic by Gabor Kiss
Leptons and Quarks (top) and three forces of nature (bottom): From “A Unified Theory of Elementary Particles and Forces” by Howard Georgi, in Scientific American, April 1981. Graphics by Gabor Kiss
Supersymmetry posits that for every ordinary particle there exists a “superpartner”: From “Is Nature Supersymmetric?” by Howard E. Haber and Gordon L. Kane, in Scientific American, June 1986. Graphic by Gabor Kiss
The three families of fundamental particles: From “The Number of Families of Matter” by Gary J. Feldman and Jack Steinberger, in Scientific American, February 1991. Graphic by Ian Worpole
Characters of the Standard Model: From “The Discovery of the Top Quark” by Tony M. Liss and Paul L. Tipton, in Scientific American, September 1997. Graphic by Michael Goodman
Masses of the particles of the Standard Model: From “The Mysteries of Mass” by Gordon Kane, in Scientific American, July 2005. Graphic by Bryan Christie Design
The basics of particle physics: From “The Coming Revolutions in Particle Physics” by Chris Quigg, in Scientific American, February 2008. Graphic by SlimFilms
To learn more about the premise and problems of the Standard Model of particle physics, see the CERN (European Organization for Nuclear Research) website, “The Dawn of Physics beyond the Standard Model” By Gordon Kane (Scientific American, January 2006), and “Could the Higgs Nobel Be the End of Particle Physics?” By Harry Cliff (October 2013).