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Von Neumann's mathematical analysis of the structure of self-replication preceded the discovery of the structure of DNA. In a short list of facts about his life he submitted to the National Academy of Sciences, he stated "The part of my work I consider most essential is that on quantum mechanics, which developed in Gottingen in 1926, and subsequently in Berlin in 19271929. Also, my work on various forms of operator theory, Berlin 1930 and Princeton 19351939; on the ergodic theorem, Princeton, 19311932."

Von Neumann's study of what preceded the discovery of DNA?
mathematical analysis of the structure of self-replication