Alan Turing Centenary

'Alan Turing'
Artist: Stephen Kettle
Title: Alan Turing
Material: stacked slate
photo: Leo Reynolds

Bletchley Park National Codes Centre
Bletchley Park, Milton Keynes, Buckinghamshire, England, UK

Alan Mathison Turing, OBE, FRS (23 June 1912 – 7 June 1954), mathematician, cryptanalyst, computer scientist, prophet and hero, would have been 100 today. He is someone I would like to portray, but I have been stumped. My scientists are shown with images of something quintessential to their science, or the reason they are famous (or should be), but Turing had so many accomplishments, it isn't obvious what to portray or how. You might recall his portrayal in Neal Stephenson's Cryptonomicon. I was introduced to him many year ago by Douglas Hofstadter's  Gödel, Escher, Bach (which I can't recommend highly enough... go read it now). You may be familiar with the Turing Test or at least its portrayal in Blade Runner. Turing foresaw not only that machines might quite likely develop the capacity to think (after all, our brains are only made of matter, and complex systems of neurons, which either fire or not, much like an electronic switch), but that we needed an objective, double-blind test to determine whether something/someone was able to think, as early as 1950, when most people were only dimly aware of the existence of any sort of computer. But Turing quite literally defined what we now mean by computation itself (with his concept of Turing Machines) back in 1936. During the WWII he worked as a codebreaker and invented the device which was finally able to crack the notorious German crypotographic Enigma machine! His work undoubtedly saved many lives, and today we recognize him as a genius and a hero. During his all too short life, he also made important contributions to mathematical biology and explaining morphogenesis (the biological process that causes an organism to develop its shape) and the existence of Fibonacci numbers in biology. 

Tragically, he lived in a time even more biased and bigoted than our own. Rather than recognizing the magnitude of his contributions to society during his lifetime, he was prosecuted for his homosexuality (still illegal in Britain in 1952) and forced to undergo chemical castration. He died two years later, after eating a cyanide-poisoned apple (determined by the coroner to be a suicide). It is truly abominable they way he was treated; while we can't address the past injustice we can remember, recognize and celebrate his remarkable achievements today.

Check out this Turing Machine built from LEGO, in honour of the 2012 Turing Year!

(via Brain Pickings, which also has an interesting article about Turing) 

This beautiful paper Turing Machine, by The Real M Davey employs a microcontroller and some electronics, but it is really the paper itself which is the computer (as the "tape" is described in Turing's original paper:

My goal in building this project was to create a machine that embodied the classic look and feel of the machine presented in Turing’s paper. I wanted to build a machine that would be immediately recognizable as a Turing machine to someone familiar with Turing’s work. Although this Turing machine is controlled by a Parallax Propeller microcontroller, its operation while running is based only on a set of state transformations loaded from an SD card and what is written to and read from the tape. While it may seem as if the tape is merely the input and output of the machine, it is not! Nor is the tape just the memory of the machine. In a way the tape is the computer. As the symbols on the tape are manipulated by simple rules, the computing happens. The output is really more of an artifact of the machine using the tape as the computer.

(↬ Adafruit blog)

You can also learn how to make a papercraft Enigma machine on MAKE.