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Murray Gell-Mann, Who Peered at Particles and Saw the Universe, Dies at 89
Murray Gell-Mann, who transformed physics with his preternatural ability to find hidden patterns among the tiny particles that make up the universe, earning a Nobel Prize, died on Friday at his home in Santa Fe. He was 89.
Jenna Marshall, a spokeswoman for the Santa Fe Institute, where he held the title of distinguished fellow, announced his death.
Much as atoms can be slotted into the rows and columns of the periodic table of the elements, Dr. Gell-Mann found a way, in 1961, to classify their smaller pieces — subatomic particles like protons, neutrons, and mesons, which were being discovered by the dozen in cosmic rays and particle accelerator blasts. Arranged according to their properties, the particles clustered in groups of eight and 10.
In a moment of whimsy, Dr. Gell-Mann, who hadn’t a mystical bone in his body, named his system the Eightfold Way after the Buddha’s eight-step path to enlightenment. He groaned ever after when people mistakenly inferred that particle physics was somehow related to Eastern philosophy.
Looking deeper, Dr. Gell-Mann realized that the patterns of the Eightfold Way could be further divided into triplets of even smaller components. He decided to call them quarks after a line from James Joyce’s “Finnegans Wake”: “Three quarks for Muster Mark.”
With Dr. Gell-Mann at the forefront, physics took on a Joycean feel. Before long there were up quarks and down quarks, strange quarks and charm quarks, top quarks and bottom quarks, all stuck together with particles called gluons. The funny nomenclature was as much a Gell-Mann inspiration as the mathematics.
“Murray Gell-Mann dominated theoretical particle physics during the 1950s and ′60s, a period with an abundance of new experimental discoveries,” his colleague David J. Gross, another Nobel laureate in physics, said in an interview for this obituary in 2010. “With almost magical intuition Gell-Mann discerned the patterns and symmetries connecting the many new particles that were found.”
Conversant in several languages and fascinated by archaeology, linguistics, natural history and ornithology, Dr. Gell-Mann spotted and named subatomic phenomena as eagerly as if they were exotic birds.
“Our work is a delightful game,” he said at the Nobel banquet in Stockholm, where he received the prize for physics in 1969. “I am frequently astonished that it so often results in correct predictions of experimental results.”
After comparing the simple structure of a mathematical formula to the rules of the sonnet, he surprised his hosts by finishing his speech in Swedish. (He later berated himself for mispronouncing a word.)
With his hyphenated surname and cosmopolitan ways, Dr. Gell-Mann liked to keep people wondering about his pedigree. The physicist Sheldon Glashow once recalled a party at which his colleague cagily spun a tale about the confluence in Scotland of the River Gell and the River Mann.
Dr. Gell-Mann also had a compulsion, upon meeting new people, to provide them with the etymology and proper pronunciation of their names, going on to expound on seemingly any subject under the sun. Some found him charming, others exasperating. No one doubted the immensity of his mind.
He was born on Sept. 15, 1929, in Lower Manhattan to Arthur and Pauline (Reichstein) Gell-Mann, both Eastern European immigrants. At the time, his father operated a language school. (Born Isidore Gellmann in a small town in what was then Galicia, near the Russian border, the elder Mr. Gell-Mann had studied mathematics and philosophy in Vienna. He changed his name to Arthur and apparently added the hyphen sometime after 1911, when he was called to New York by his parents, who had emigrated earlier and were having financial problems.)
During the Depression, the language school failed and the family, which included an older son, Ben, moved to cheaper quarters on 188th Street in the Bronx, near the Bronx Zoo, and later to the Upper West Side of Manhattan.
This was long before the time when an apartment in the neighborhood conferred a prestigious address. In an oral history interview, Dr. Gell-Mann recalled living in hard times. His father, he said, though intellectually curious, struggled to make a living, finding a back-office job on Wall Street, working for a toy importer and, finally, securing a position at a bank “at a very low salary.”
“We had very little money,” Dr. Gell-Mann said.
Young Murray was already showing signs of precociousness, multiplying large numbers in his head and correcting his elders on the pronunciation of foreign words. With the encouragement of his mother and help from a piano teacher who gave lessons at a local settlement house, he won a scholarship to Columbia Grammar, a private school on West 93rd Street, where he earned the nickname “the Walking Encyclopedia.”
Graduating as valedictorian at age 14, he went to Yale, also on scholarship. But physics was not his first choice as a major area of study, he said in the oral history. He considered archaeology or a field related to natural history. His father, however, pushed him to choose engineering, saying it would lead to a well-paying job. Murray resisted, and they settled on physics as a compromise — “to please the old man,” Dr. Gell-Mann said — and he soon found that the subject fascinated him.
“My father was absolutely right,” he said.
After Dr. Gell-Mann earned his doctorate at the Massachusetts Institute of Technology, in 1951, J. Robert Oppenheimer, who had directed the Manhattan Project, brought him to the Institute for Advanced Study in Princeton, N.J. From there he went to the University of Chicago and worked under Enrico Fermi.
The two decades after World War II were a golden age in physics, with experimenters discovering one new phenomenon after another for theorists to explain. Some particles bombarding the earth as cosmic rays seemed to defy the known laws of physics: They did not disintegrate nearly as quickly as the equations predicted. Dr. Gell-Mann showed that this behavior could be explained by positing a new physical quality, which he named “strangeness.”
As with energy, there is a law of conservation of strangeness. (It is conserved in strong interactions and electromagnetic interactions but not in weak interactions.) Once this was taken into account, physicists could explain the particle’s surprisingly slow decay.
In 1955 Dr. Gell-Mann married J. Margaret Dow, an archaeology assistant he had met during a visit back to Princeton. Lured by an offer from the California Institute of Technology, the couple moved to Pasadena, where they raised two children, Elizabeth and Nicholas. The renowned physicist Richard Feynman was also at Caltech, and the two men, their egos clashing, collaborated for a while before Dr. Gell-Mann struck out on his own.
As with strangeness, the Eightfold Way and quarks were independently discovered by other theorists, but the breadth of Dr. Gell-Mann’s accomplishments and his flair for nomenclature ensured that his would be the name most remembered.
His instincts weren’t infallible. At first he dismissed quarks as mathematical abstractions — an accounting device with no real correlate in the physical world. There was good reason for his skepticism: Quarks would have to have electrical charges measured in thirds, something that was never observed.
After quarks were confirmed indirectly in an experiment at the Stanford Linear Accelerator Center, in Menlo Park, Calif., Dr. Gell-Mann denied that he had ever doubted their existence. He went on to help explain how the tiny particles are permanently stuck together, keeping their fractional charges hidden from view. A “green” quark, a “red” quark and a “blue” quark (the labels were arbitrary) blended to form a “colorless” proton. It was Dr. Gell-Mann who named the theory quantum chromodynamics.
By this time he was becoming known for his abrasive style, cutting down colleagues with withering remarks or saddling some of them with derisive names. The physicist Abraham Pais became “the evil dwarf.” The renowned experimenter Leon Lederman (who died last October) was “the plumber.” But those who could abide Dr. Gell-Mann’s prickliness found the intellectual pugilism exciting.
“To work with him it helps first of all not to have too fragile an ego,” James Hartle, a former student and collaborator, said in a remembrance in 2014, when Dr. Gell-Mann received the prestigious Helmholtz Medal, established in 1892. (Past recipients included Lord Kelvin and Robert Bunsen.) “But despite the obvious differences in intellect and insight, Murray somehow makes you feel an equal partner when you are working with him.”
Dr. Gell-Mann was an early champion of superstrings, hypothetical particles that, if ever verified, would be even more fundamental than quarks. Later in his career he began thinking in other directions, puzzling over the way simple laws of physics give rise to the beauty and intricacy of the living world. He explored the idea in a popular book, “The Quark and the Jaguar: Adventures in the Simple and the Complex” (1994).
In 1992, a little more than a decade after his wife, Margaret, died of cancer, he married Marcia Southwick, a poet he had met in Aspen, Colo., where he had a summer home. After retiring from Caltech, he moved with her to New Mexico, where he and several colleagues had founded the Santa Fe Institute in 1984. The marriage ended in divorce. He is survived by his two children and by a stepson, Nicholas Southwick Levis.
By the time Dr. Gell-Mann learned he would receive the Helmholtz Medal from the Berlin-Brandenburg Academy of Sciences and Humanities, he was in a wheelchair accompanied by an attendant. So the academy came to him, bestowing the prize in a ceremony at the Santa Fe Institute.
Afterward, Dr. Gell-Mann’s friend, the novelist Cormac McCarthy, raised a champagne toast. During the ceremony, Dr. Gell-Mann had been described as “one of the great physicists of the latter half of the 20th century.” Mr. McCarthy objected to the qualification. Dr. Gell-Mann, he said, is “undoubtedly one of the great scientists of the 20th century.”
In a talk in 2007, Dr. Gell-Mann compared the last century of physics to pulling back the skins of an onion, finding at every layer that the same mathematics applies — and hinting that an objective reality can conceivably be explained someday by a universal set of laws.
“Somewhere on some other planet orbiting some very distant star, maybe in another galaxy, there could well be entities that are at least as intelligent as we are,” he said. “Suppose they have very different sensory apparatus — they have seven tentacles, and they have 14 funny-looking little compound eyes and a brain shaped like a pretzel.” Nevertheless, Dr. Gell-Mann said, we can be confident that these creatures would discover the same fundamental laws. Some people believe otherwise, he added, “and I think that is utter baloney.”
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