Alan Turing
 Alan Turing    | |
|---|---|
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| Born | Alan Mathison Turing 23 June 1912 |
| Died | 7 June 1954 (Age 41) |
Alan Turing {23 June 1912 – 7 June 1954) was an English computer scientist, mathematician, logician, cryptanalyst, philosopher and theoretical biologist.
Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general purpose computer.[1] Turing is widely considered to be the father of theoretical computer science and artificial intelligence.
Contents
Wartime codebreaking
During the Second World War, Turing worked for the Government Code and Cypher School (GC&CS) at Bletchley Park, Britain's codebreaking centre that produced Ultra intelligence. For a time he led Hut 8, the section which was responsible for German naval cryptanalysis. Here he devised a number of techniques for speeding the breaking of German ciphers, including improvements to the pre-war Polish bombe method, an electromechanical machine that could find settings for the Enigma machine. Turing played a pivotal role in cracking intercepted coded messages that enabled the Allies to defeat the Nazis in many crucial engagements, including the Battle of the Atlantic, and in so doing helped win the war. A number of sources state that Winston Churchill said that Turing made the single biggest contribution to Allied victory in the war against Nazi Germany. However both The Churchill Centre and Turing's biographer Andrew Hodges have said they know of no documentary evidence to support this claim nor of the date or context in which Churchill supposedly said it, and the Churchill Centre lists it among their Churchill 'Myths',[2][3] A BBC News profile piece that repeated the Churchill claim has subsequently been amended to say there is no evidence for it.[4] Counterfactual history is difficult with respect to the effect Ultra intelligence had on the length of the war,[5][6] but at the upper end it has been estimated that this work shortened the war in Europe by more than two years and saved over fourteen million lives.[7]
Post-war computing
After the war, Turing worked at the National Physical Laboratory, where he designed the Automatic Computing Engine (ACE), among the first designs for a stored-program computer. In 1948 Turing joined Max Newman's Computing Machine Laboratory at the Victoria University of Manchester, where he helped develop the Manchester computers and became interested in mathematical biology. He wrote a paper on the chemical basis of morphogenesis, and predicted oscillating chemical reactions such as the Belousov–Zhabotinsky reaction, first observed in the 1960s.
Homosexuality
Turing was prosecuted in 1952 for homosexual acts, when by the Labouchere Amendment, "gross indecency" was criminal in the UK. He accepted chemical castration treatment, with DES, as an alternative to prison. Turing died in 1954, 16 days before his 42nd birthday, from cyanide poisoning. An inquest determined his death as suicide, but it has been noted that the known evidence is also consistent with accidental poisoning.[8]
Apology and pardon
In 2009, following an Internet campaign, British Prime Minister Gordon Brown made an official public apology on behalf of the British government for "the appalling way he was treated." Queen Elizabeth II granted him a posthumous pardon in 2013.[9][10]
The Alan Turing law is now an informal term for a 2017 law in the United Kingdom that retroactively pardoned men cautioned or convicted under historical legislation that outlawed homosexual acts.[11]
References
- ↑ Newman, M. H. A. (1955). "Alan Mathison Turing. 1912–1954". Biographical Memoirs of Fellows of the Royal Society. 1: 253–263. doi:10.1098/rsbm.1955.0019. JSTOR 769256.Page Module:Citation/CS1/styles.css must have content model "Sanitized CSS" for TemplateStyles (current model is "Scribunto").
- ↑ Schilling, Jonathan. "Churchill Said Turing Made the Single Biggest Contribution to Allied Victory". The Churchill Centre: Myths. Retrieved 9 January 2015.Page Module:Citation/CS1/styles.css must have content model "Sanitized CSS" for TemplateStyles (current model is "Scribunto").
- ↑ Hodges, Andrew. "Part 4: The Relay Race". Update to Alan Turing: The Enigma. Retrieved 9 January 2015. Italic or bold markup not allowed in:
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- ↑ Hartcup, Guy (2000). The Effect of Science on the Second World War. Basingstoke, Hampshire: Macmillan Press. pp. 96–99.Page Module:Citation/CS1/styles.css must have content model "Sanitized CSS" for TemplateStyles (current model is "Scribunto").
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