Nobel-winning scientist and one of the most influential physicists of the 20th century

Born: September 15 1929;

Died: May 24 2019

MURRAY Gell-Mann, who has died aged 89, was one of the greatest physicists of the last century and perhaps the most important in the construction of the Standard Model, which attempts to explain the behaviour of subatomic particles; he received the 1969 Nobel Prize for his work on the understanding of elementary particles.

Any one of Gell-Mann’s contributions might have crowned the career of another scientist; he developed the concepts of “strangeness”; produced an explanation for the weak interaction; correctly predicted (and named) gluons and quarks, and was a pioneer in quantum mechanics, string theory, the seesaw theory of neutrino masses, and complexity research. In the last, his interests extended far beyond physics into, amongst other fields, the evolution and development of language.

A pedantic and frequently cantankerous polymath and perfectionist with a mop of curly hair, Gell-Mann made little attempt to accommodate those he thought intellectually inferior. He seldom held back from harsh judgments, and would immediately correct any perceived error; he was known to upbraid strangers for mispronouncing, in his view, their own names. But the writer Cormac McCarthy, who became a friend and colleague at the Santa Fe Institute Gell-Mann founded, thought he “knew more things about more things than anyone I’ve ever met”, and he was notable, too, for his readiness, in accordance with the scientific principle, to concede on the rare occasions when his work was shown to be wrong.

Murray Gell-Mann was born in lower Manhattan, New York, on September 15 1929. His parents were Jewish; nominally Austro-Hungarian immigrants, though they hailed from Czernowitz in what is now Ukraine.

Murray’s older brother Benedict, taught Murray to read and write, and shared his own enthusiasms, which included bird-watching, photography and language. Murray attended Columbia Grammar, a private school on the upper West Side, on a full scholarship, and the range of his interests and depths of his understanding were immediately evident; at the age of 14, he was accepted to Yale.

There, he came second in the mathematics competition and graduated in physics in 1948, though he was frustrated when applying to Ivy League colleges for graduate studies; Yale would take him only in maths, Harvard offered no scholarship, and Princeton rejected him outright. He considered suicide, but instead went to the Massachusetts Institute of Technology, reckoning, with faultless logic, that he could go there, and then kill himself, but not the other way round.

He gained his PhD, supervised by Victor Weisskopf, who had led the theoretical division of the Manhattan Project which developed the atomic bomb, then in 1951 spent a year at the Institute for Advanced Study at Princeton, where he was on nodding terms with Albert Einstein, though they never spoke.

In 1952, Gell-Mann joined the group at the University of Chicago led by Enrico Fermi, who had discovered both the neutrino and the weak interaction (with gravity, electromagnetism and the strong force, one of the four fundamental interactions between particles).

There was at the time huge competition amongst nuclear scientists to describe the behaviour of numerous new subatomic particles hypothesised by theoretical quantum electrodynamics and, increasingly, confirmed by the particle accelerators of the experimental physicists. Gell-Mann turned his attention to V-particles, and began to speculate that there must be an undetected force (which he initially called y) similar to a charge, which was conserved by the strong and electromagnetic forces, but not the weak force.

The algebraic structure he devised for this theory provided not merely a description, but an explanation for families of particles; it also became apparent to him that there were obvious missing members in this family. From 1953, he published papers arguing that “strangeness” (as he had renamed y) explained with a quantum number why some hadrons decayed rapidly and others more slowly – relatively speaking, since the times involved were hundreds of millionths of a second. He was also able to predict specific particles not yet observed.

His ideas, entirely independently proposed at around the same time by the Japanese physicist Kazuhiko Nishijima, were triumphantly vindicated by experiments and “strangeness” caught on as the name. Many physicists initially disliked Gell-Mann’s fanciful terms – colour, flavour, quark and “eightfold way”, amongst others – but his nomenclature was so memorable it tended to win out.

After Fermi’s death in 1954, Gell-Mann moved to the California Institute of Technology, where his colleagues included Richard Feynmen. The two worked together on the V-A theory of the weak interaction, publishing in 1958, though their relationship was sometimes strained. Gell-Mann admired Feynman’s work, but not his impulse for showmanship.

In 1961, Gell-Mann proposed a new classification for hadrons in the strong interaction, which arranged them in symmetrical octets, and which he jokingly called the “eightfold way” after the Buddhist doctrine. It has been described as as important in particle physics as the periodic table is for chemical elements.

By 1964, this scheme had led him to posit the existence of “quarks”, the particles of which such hadrons were composed. George Zweig independently came up with a similar theory (calling them “aces”), but Gell-Mann’s name again was adopted. Quark (pronounced quork) was taken from a line in Finnegans Wake, James Joyce’s deliberately obscure novel/crossword puzzle, which read “Three quarks for Muster Mark!”

He remained Professor of Theoretical Physics at Caltech until his retirement in 1993, but also set up the Santa Fe Institute in New Mexico, which conducted research in the bewildering range of fields that interested him. These included wildlife (he was a keen hiker and birdwatcher), archaeology, the evolution of language and psychology. With the writer Michael Crichton, he anticipated “fake news”, and came up with the Gell-Mann amnesia effect, which tried to explain why people believe news stories about which they have no expertise, even when published alongside reports about their own field that they know to be false.

Murray Gell-Mann married, in 1955, Margaret Dow, with whom he had a son and a daughter. She died in 1983 and in 1992 he married Marcia Southwick, with whom he had a stepson, though the marriage was later dissolved. In his later years, his companion was Mary McFadden, with whom he published a book on art, fashion and design.