Jessica MacNeil
EDN
Alan Turing was the father of computer science and his Turing machine laid the groundwork for the modern computer.
Born in London on June 23, 1912, the mathematician and scientist took an interest in both subjects early on. He studied mathematics at King's College, Cambridge, the received a PhD from Princeton University in 1938.
Turing became a mathematician who studied logic and the questions of mind and matter. He became interested in the Entscheidungsproblem (German for "decision problem") of David Hilbert, which called for an algorithm that uses a first-order logic statement as input and determines whether it is universally valid with a yes or no answer.
His famous paper "On Computable Numbers, with an Application to the Entscheidungsproblem," published in Proceedings of the London Mathematical Society in 1936, laid out concepts applicable today that became the basis for computer science, and laid the plans for the electronic digital computer.
Turing conceived of a simple machine similar to a typewriter that was capable of reading single-character instructions encoded on a tape, that would replicate logical human thought. That idea would become the Turing machine, a model of a general purpose computer that proved a machine could do any mathematical computation if it could be represented by an algorithm. The machine proposal was the first to include functions determined by a program stored in memory.
During World War II, Turing led the team responsible for German naval cryptanalysis at the Bletchley Park center for codebreaking. His decryption device, The Bombe, developed with Gordon Welchman, was able to decode the German Naval Enigma, which played a major role in the Allied victory. At that time, Turing also developed a method to encode and decode telephone conversations that contributed to Bell Labs' SIGSALY system, used to secure Allied communication.
After the war he designed the ACE (Automatic Computing Engine), a stored-program computer, while working at the National Physical Laboratory. A simplified model, the ACE Pilot Model was built in 1950 (see image below) and became the first electronic computer. It was the fastest computer in the world at 1 MHz, and used mercury delay lines able to store 32 bits of data.
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| The ACE Pilot Model built at the National Physcial Laboratory in 1950. | |
In 1948, Turing joined the University of Manchester and began working on software for the Manchester Mark 1 computer. He also published "Computing machinery and intelligence" in 1950, which established the Turing test, a standard to determine if a machine is intelligent. He was also interested in mathematical biology and in 1952, Turing published "The Chemical Basis of Morphogenesis."
Turing was prosecuted for homosexual activity in 1952. When convicted, he chose to receive chemical treatment to avoid time in prison, and lost his security clearance to work on government projects. He received a royal pardon from the Queen more than 60 years later, in 2013.
The brilliant mathematician died on June 7, 1954, at age 41, from cyanide poisoning. While it was ruled a suicide, some believe he accidentally inhaled fumes from a chemical experiment he had set up.
