'Alan Turing' £50 note goes into circulation

The Bank of England has released a £50 note featuring Enigma code breaker Alan Turing

The Bank of England has released a new £50 note featuring noted computer scientist and wartime code breaker Alan Turing.

The new polymer-based note will replace the previous paper version featuring portraits of steam-age engineers James Watt and Matthew Boulton, which will be withdrawn from circulation in September.

The £50 note makes up about one in 13 of the banknotes in circulation in the UK.

The release date, 23^rd June, coincides with Turing's birthday.

Born in London in 1912, over his short lifetime Alan Turing excelled as a mathematician, logician and a prime mover of the concepts of algorithms, computing machines, stored computer programs, encrypted voice communications and artificial intelligence.

The work for which he is best known, of course, was leading the effort at Bletchley Park to crack military messages encrypted using the German Enigma machine, which almost certainly helped to shorten the Second World War.

Despite his talents, according to his colleague Captain Jerry Roberts, Turing was never one for the limelight.

"The extraordinary thing is that, this quiet man was probably the most important man of his time, except possibly Churchill. Turing did not look like a superstar, he was a very modest man, but Turing was the genius who broke Naval Enigma," he said.

Among computer scientists he is almost as well known for his earlier work in the 1930s on what became known as the Turing Machine, a theoretical, algorithm-based model of computation and one of the foundational models of computer science.

After the war, he designed the Automatic Computing Engine (ACE), one of the earliest computer program concepts, and became deputy director of the Computing Laboratory at Manchester University, where he became interested in artificial intelligence and theoretical mathematics.

However, in 1952 he was arrested on a charge of gross indecency, after having an affair with a 19-year-old man in Manchester, and was forced to take female hormones to ‘cure' his homosexuality, and as an alternative to prison.

Turing committed suicide in 1954 at the age of 41. It was not until 2013 that he was granted a posthumous royal pardon.