Word: quarks
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...charms of the quark...
...down into discrete particles, the protons and neutrons, and since then a great many related particles have been identified. During the past decade it has become apparent that those particles too are complex rather than elementary. They are now thought to be made up of the simpler things called quarks. A solitary quark has never been observed, in spite of many attempts to isolate one. Nevertheless, there are excellent grounds for believing they do exist. More important, quarks may be the last in the long series of progressively finer structures. They seem to be truly elementary...
...attempt to bring some order to the unruly world of hadrons, Murray Gell-Mann, a physicist at the California Institute of Technology, proposed the quark theory. All hadrons, said Gell-Mann in 1963, can be composed of two or three quarks or their anti-particles. Quarks come in three "flavors"--up, down and sideways. Down quarks ('d') have an electric charge of -1/3, up quarks ('u') have charge + 2/3. And then there are sideways quarks ('s'). Sideways quarks are used to make "strange" particles, the ones with the long lifetimes, and are said to have "strangeness" 1. All other...
Gell-Mann's theory, modified so that each quark also comes in three different "colors" (no kidding), proved tremendouly successful. One could then describe every hadron by some quark combination, and every quark combination by an observed hadron. (A proton, for instance, is the combination 'uud.' The neutral K-meson, which has strangeness *1, is the combination...
...moves to Glashow's contribution, which came in 1964. Motivated by considerations of grace and elegance in theories which combined the electromagnetic force and a force called the "weak force" (to distinguish it from the "strong force"), Glashow and another physicist, James D. Bjorken, postulated an additional flavor of quark, and named it the "charmed" quark. Glashow writes in a New York Times article...