(Monday morning Math – this week on Friday because Hello Midterms!)

Our mathematician this week is Alan Turning. He was born in London, England, on June 23, 1912 and studied mathematics at the University of Cambridge. After his graduation he wrote a paper called “On Computable Numbers, with an Application to the Entscheidungsproblem” which showed the depressing sounding but powerful result that not every true statement is provable in a mathematical system. During this time he also invented the Turing machine, which is an abstract computer (as opposed to an actual physical computer) that performs logical computations.

Turing earned his PhD at Princeton University in 1938 and returned to Cambridge where he began working on codebreaking. The following year, at the start of World War II, he moved to Bletchley Park where he developed methods for breaking various codes intercepted from the Germans and, even after the war continued to make significant contributions to work in artificial intelligence.

While Turing was recognized for his work he was also persecuted because of his sexuality: in 1952 he was convicted of being homosexual and given the choice of going to prison or taking hormones as a chemical castration. He chose the latter; he also lost his security clearance as a result of this conviction. Turning continued to do work in physics and biology, but died on June 7, 1954, from self-induced cyanide poisoning. In 2009 the British government officially apologized for how they treated him and in 2013 Turing was posthumously pardoned.

You can find more information about Alan Turing at Britannica, Wikipedia and turing.org.uk And to end on a more positive note, these days there is Spectra, the Association for LGBTQ+ mathematicians and their allies.

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