|Alfred Horn, Palisadian
and Noted UCLA Math Professor
This article originally appeared in the Palisades Post. Displayed with permission.
Alfred Horn, a professor of mathematics at UCLA from 1947 until his retirement in 1988, died at home in Pacific Palisades on April 16, after an eight-year battle with prostate cancer.
Professor Horn published 35 papers during his career, mostly in the areas of lattice theory and universal algebra. Among the highlights of his research is a 1962 paper on linear algebra titled "Eigenvalues of sums of Hermitian matrices," in which he makes a conjecture, the last step of which he lived to see proved by another UCLA mathematician in 1998. His papers leap from one area of mathematics to another, so it is difficult to judge his contribution by the simple number of papers he published.
He will probably be most remembered for another paper titled "On sentences which are true of direct unions of algebras," published in 1951. This paper describes Horn sentences and Horn clauses, which became important in the 1970s in computational logic used for computer programming. Today, Horn sentences are mentioned in undergraduate texts on the subject and a search for them on Google.com results in thousands of hits. Professor Horn was amused to hear of this application for his research but he never owned a personal computer himself and had little interest in searching the Internet for news of himself or for anything else. He believed all worthwhile information could most easily be obtained at the public library.
In addition to his research, Professor Horn is remembered by generations of his students and colleagues as an effective, kind and modest teacher who gave brilliant lectures and mentored many graduate students who went on to have successful careers of their own. Several of his former students spoke fondly of him at a memorial service held at the UCLA Mathematics Department on April 20.
Alfred Horn was born February 17, 1918, on the Lower East Side of New York City. His parents were both deaf and he was the oldest of three hearing children. His father died when he was three years old and he and his siblings moved in with his maternal grandparents, Morris and Ida Krinsky, who had emigrated to America from Russia in 1893 with seven children. Ida carried her daughter Esther, Alfred's mother, in her arms (even though Esther was already eight years old) through customs at Castle Garden as she was afraid American officials would send Esther back to Europe if they discovered she was deaf.
Alfred was raised in this large extended family by his aunts, uncles and elderly grandparents. Morris Krinsky, a tailor, was able to move the family to a house in Brooklyn, and Alfred had many happy memories of life there - visiting Coney Island, playing football and punchball in the street, being taken to see a semi-pro baseball team called the Sons of David whose players all wore beards, and listening to opera on the radio. He contributed to the family finances in high school by working as a printer's devil on The Running Horse, a racing form published by one of his uncles. He also pushed racks of material in the Manhattan garment district, tended a newsstand on Sundays, and worked in a subway token booth.
He lived at home while he went to college at CCNY and NYU, where he earned a master's degree in mathematics. Then he took the train in California, playing poker in the club car to while away the time, to get his Ph.D. from Berkeley in 1946.
During World War II, he worked at the Lawrence Radiation Lab in Berkeley, solving mathematical problems relating to work on a new weapon. He learned of the physics of the atomic bomb only after it was dropped on Hiroshima, when he remembers E. O. Lawrence (inventor of the cyclotron) announcing in the hallway that, "This means the end of war." Professor Horn remembered, "Even then, I knew he was wrong."
In 1945, he married a fellow graduate student at Berkeley, Carole Christiansen, a psychology major from North Dakota. They had two children: Karen, married to Michael Shore, who is now a film teacher and writer living on Topanga, and Julian, married to Laura Gawronski, who is a software engineer in Acton, Massachusetts. Michael's daughter, Julie Shore, is Horn's only grandchild. All his family survive him.
In addition to his mathematical work, Alfred enjoyed listening to his complete collection of the works of Mozart (first assembled on 78's, later replaced by LP's-he refused to do it a third time on cassettes or CD's), and adding to his impressive collection of stamps from the French colonies and American commemorative. For his sabbatical year in 1953 he was at Princeton, and thereafter he spent sabbaticals in Berkeley, MIT in Boston, and in London.
He bought his house in Pacific Palisades in 1954 and lived there continuously until his death. His favorite place in the village was the Palisades branch library, and he will be remembered there as a constant visitor.
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