US physicist, who proposed the concepts of strangeness and quarks and predicted the existence of the omega-minus particle. For his contributions to particle physics he was awarded the 1969 Nobel Prize for Physics.
The son of Austrian immigrants, Gell-Mann was born in New York and educated at Yale and the Massachusetts Institute of Technology, where he gained his PhD in 1951. He taught at Chicago for four years before moving in 1955 to the California Institute of Technology, where he had been appointed professor of physics at the age of twenty-six. His first major contribution to high-energy physics was made in 1953, when he demonstrated how some puzzling features of hadrons (particles responsive to the strong force) could be explained by a new quantum number, which he called ‘strangeness’.
He also made extensive use of group theory in a most original manner to create order among the increasing number of known particles, forming them into a number of natural families. Gell-Mann's insight was supported by the discovery of the omega-minus particle and others, which his groupings had predicted in the previous year. Having introduced some order into an increasingly complex field, Gell-Mann attempted a measure of simplification by assuming that all hadrons consisted of groups of fractionally charged particles, which he called quarks (a name taken from a quotation in James Joyce's Finnegans Wake: ‘Three quarks for Muster Mark’). Gell-Mann proposed that all particles could be reduced to combinations of at most three quarks, although the number of quarks and their antiparticles has since been increased. The quark hypothesis is still widely accepted.
Subjects: Science and Mathematics.