“Three quarks for Muster Mark!”
In the decade that followed the discovery of the antiproton (1956), the particle zoo spiraled out of control. However, if there was one person who put order to all this chaos, it was Murray Gell-Mann. In 1964, Gell-Mann proposed that there were even more fundamental particles beyond the protons and neutrons; he called them quarks, from the phrase “Three quarks for Muster Mark!” in James Joyce's novel Finnegans Wake. This was given little attention; Gell-Mann himself didn’t press the matter much; he knew it would be very difficult to prove. But in 1968 a group working under Elliot Bloom at the Stanford Linear Accelerator Center (SLAC) managed to infer the presence of quarks by shooting high energy electrons at them. This was closely analogous to Rutherford's gold-foil experiment: they saw hard deflections at angles that did not make sense if the proton were a cloud-like object—meaning there were small, hard, point-like things inside the proton. Those scattering centers were Gell-Mann’s quarks. But still, some doubt lingered. Then, in November 1974, a heavier “charm” quark and its antiquark were discovered simultaneously at SLAC and Brookhaven. After that, the reality of quarks was hard to argue with, and the remaining types (charm, bottom, top) were pinned down over the following decades. The last quark, the up, was found on March 2, 1995, at Fermilab's Tevatron (a synchrotron accelerator with an energy of 1.8 trillion electron volts, hence the name). This completed the list of all fundamental Fermions, the particles that make up all physical matter in the universe. All matter (the whole particle zoo) is built by quarks and electrons. There is only one more thing that completes the picture: the bosons (i.e. forces). Among these, the photon, which we had known about since the early 1900s and carry electromagnetism, the gluons, discovered in 1979 at the PETRA collider in Hamburg, and which gave us a more detailed picture of the strong nuclear force, and the W and Z bosons, carrying the weak force, found at CERN in 1983. By the turn of the millennium only one force was missing, the Higgs field…
Source: various
Image by Joi under CC BY-SA 3.0
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Full disclosure, I may occasionally borrow a sentence from Will Durant's Story of Civilization. I absolutely love that collection!