Alan Turing was a code-breaker, a computer scientist, a mathematician, an ideas man. But he was persecuted by his government and forgotten by his country.
His work on breaking the code of the German naval Enigma machines at Bletchley Park in the 1940s is credited with considerably hastening the end of World War II.
The 1945 specification he wrote for the Automatic Computing Engine (ACE) produced one of the most powerful machines in the world when the pilot model was built in 1950, and was the precursor to modern PCs.
But his life was cut tragically short – his potential unfulfilled and his legacy largely overlooked – as a result of a 1952 conviction for gross indecency, for the ‘crime’ of being a homosexual.
In this, the centenary year of his birth, (today is his birthday) Turing is finally being recognised for his impact on the history of computing, computer science, artificial intelligence, developmental biology, and the mathematical theory of computability
The London Science Museum is honouring Alan Turing with a new exhibition celebrating his life and offering “an indisputable argument for his enduring global legacy”.
Speaking at a preview of the ‘Codebreaker – Alan Turing’s Life and Legacy’ exhibition on 20 June, Sir John Dermot Turing, Alan Turing’s nephew, praised curators for bringing to life the sometimes intangible nature of his uncle’s work.
“What I think was interesting to Alan Turing was not all the mechanical cranking of numbers, but it was what the machines could actually do,” Sir John said.
“Most of what he worked on was in the realm of ideas – software, code-breaking algorithms, whether machines can think, differential equations underlying morphogenesis.
“It’s very difficult to bring that to life, but it’s gratifying that the Museum has found ways of visualising these things. It’s a great tribute to a very remarkable man.”
The exhibition includes some of the most important artefacts in the Alan Turing story, accompanied by images, objects and personal recollections that put them into context. Also on show are items that inspired Turing, and were inspired by him.
German military Enigma machines are displayed alongside the hand-written mathematical workings-out that preceded Turing’s invention of the electromechanical ‘bombe’ machine (components of which are also on display) that cracked their codes. The Pilot ACE computer sits opposite the wreckage of a Comet jet it analysed using millions of high-speed computations to determine the cause of its fatal crash.
Peter Barron, director of external relations at Google, the exhibition’s sponsors, said: “Turing’s inventions rank among the most important intellectual breakthroughs of the 20th century. In the evolution of computing, all paths trace back to Turing.”
But the tale of his ground-breaking achievements is, sadly, not complete without the story of the shameful treatment he received in the final years of his life. Turing avoided a custodial sentence for his gross indecency conviction by submitting to chemical castration by way of a 12-month course of female hormones. The exhibition includes a bottle of the synthetic oestrogen pills he was prescribed, displayed alongside the pathologist’s report that showed his stomach contained 4 ounces (enough to fill a wine glass) of cyanide following his suicide 9 months after the treatment ended.
The exhibition (which runs until 31 July 2012) also covers Turing’s later, unfinished, work on morphogenesis – the development of pattern and form in living things – and his use of mathematics to explore and try to predict those patterns.
Unfinished before his death, Turing developed a theory that the seeds in a sunflower head conform to the Fibonacci code, a sequence of numbers in which the next figure is the sum of the previous two: 1, 1, 2, 3, 5, 8, 13 and so on.
A citizen science experiment led by the Manchester Museum of Science & Industry and Manchester Science Festival, in association with The University of Manchester (the last institution at which Turing worked before his death in 1954), is this year hoping to complete Turing’s final research project.
The initial aim of ‘Turing’s Sunflowers’ was to collect 3000 sunflower heads for analysis. But by the end of May – the optimum sunflower seed-planting period – three times that many flowers had been pledged by people from 13 different countries.
“We’ve had an incredible response to our appeal to grow sunflowers to help continue Alan Turing’s fascinating study of maths in nature,” said project manager Erinma Ochu.
“There are now some 9000 sunflowers pledged to be grown around the world, and it’s particularly fitting that some of them are just beginning to bloom for Turing’s birthday.”
From around September, the end of the flowering season, participants will be asked to document or drop-off their flower heads at collection points. Mathematicians at the University of Manchester will then analyse the results to test the extent to which sunflowers follow the Fibonacci code, and try to explain why it occurs and the reasons why sometimes it doesn’t. The results will be presented during the Manchester Science Festival from 27 October – 4 November 2012.
Other ‘Turing Year’ tributes include government petitions to grant him a pardon over his 1952 gross indecency conviction and put his face on the £10 note. Blue plaques were unveiled at Cambridge and Manchester universities and his East Sussex childhood home today, and Google has dedicated a doodle to him.
As Steven Pinker, Harvard professor and popular science author, said: “It would be an exaggeration to say that the British mathematician Alan Turing explained the nature of logical and mathematical reasoning, invented the digital computer, solved the mind-body problem, and saved Western civilization.
“But it would not be much of an exaggeration.”
Pictures by Amy Freeborn, video by Alex Sterling