Gell-Mann, Murray 1929-
US theoretical physicist and Nobel Prize winner

Born in New York City, he went to Yale when he was only 15 years old, and graduated in 1948. He gained his PhD from the Massachusetts Institute of Technology (MIT), spent a year at the Institute of Advanced Studies in Princeton, then joined the Institute for Nuclear Studies at Chicago University, where he worked with Enrico Fermi. He became Professor of Theoretical Physics at the California Institute of Technology (Caltech) in 1956 then Robert Andrews Professor of Theoretical Physics (1967-93), now emeritus. When he was 24 he made a major contribution to the theory of elementary particles by introducing the concept of 'strangeness', a new quantum number which must be conserved in any so-called 'strong' nuclear interaction event. Gell-Mann and Yuval Ne'eman (independently) used 'strangeness' to group mesons, nucleons (neutrons and protons) and hyperons, and thus they were able to form predictions in the same way that Dmitri Mendeleyev had about chemical elements. The omega-minus particle was predicted by this theory and observed in 1964. Gell-Mann and George Zweig introduced the concept of quarks which have one-third integral charge and baryon number. (The name 'quark' is an invented word, associated with a line in James Joyce's Finnegans Wake.) Six quarks have been predicted, and five have so far been indirectly detected: the six are named as Up, Down, Strange, Charm, Bottom and Top. For this work he was awarded the Nobel Prize for physics in 1969. In 1994 he published The Quark and the Jaguar.