Alan Turing to appear on new £50 note

The polymer £50 note, feature Turing on its reverse, is expected to enter circulation by the end of 2021. 

In 2018, the Bank's Banknote Character Advisory Committee – which decides who appears on notes – chose to celebrate the field of science on the new £50. A six-week public nomination period led to a total of 227,299 suggestions, covering 989 eligible characters.

Twelve of the nominations (some of which were pairs of scientists) were then put forward to Mark Carney, Bank of England governor. They were Mary Anning, Paul Dirac, Rosalind Franklin, William and Caroline Herschel, Dorothy Hodgkin, Ada Lovelace and Charles Babbage, Stephen Hawking, James Clerk Maxwell, Srinivasa Ramanujan, Ernest Rutherford, Frederick Sanger and Alan Turing. 

A concept design of the note can be seen above but the full design including all the security features will be unveiled closer to it entering circulation. 

For some of the rejected nominees, see our Gareth Southgate, Danny Dyer and Nicki Minaj among rejected nominees for new £50 note MSE News story.

Who is Alan Turing?

Alan Turing is widely considered as the father of computer science and provided the theoretical underpinnings for the modern computer.

While best known for his work devising code-breaking machines during WWII, Turing played a pivotal role in the development of early computers first at the National Physical Laboratory and later at the University of Manchester. He set the foundations for work on artificial intelligence by considering the question of whether machines could think.

Turing was homosexual and was posthumously pardoned by the Queen having been convicted of gross indecency for his relationship with a man. The Bank of England says his legacy continues to have an impact on science and society today.

What will be on the £50 note?

The note will feature:

• A photo of Turing taken in 1951 by Elliott & Fry which is part of the Photographs Collection at the National Portrait Gallery. 

• A table and mathematical formulae from Turing's seminal 1936 paper 'On Computable Numbers, with an application to the Entscheidungsproblem, Proceedings of the London Mathematical Society'.

  This paper is widely recognised as having laid the foundations for computer science. 

• The Automatic Computing Engine (ACE) Pilot Machine which was developed at the National Physical Laboratory as the trial model of Turing's pioneering ACE design. The ACE was one of the first digital computers that could store a program in electronic memory.

• Technical drawings for the British Bombe, the machine specified by Turing, and one of the primary tools used to break Enigma-encoded messages during WWII.

•  A quote from Turing, given in an interview to The Times on 11 June 1949: "This is only a foretaste of what is to come, and only the shadow of what is going to be."

• Turing's signature from the visitors' book at Bletchley Park in 1947, where he worked during WWII. 

• Ticker tape depicting Turing's birth date (23 June 1912) in binary code. The concept of a machine fed by binary tape featured in Turing's 1936 paper. 

What does the Bank of England say?

Mark Carney said: "Alan Turing was an outstanding mathematician whose work has had an enormous impact on how we live today.

"As the father of computer science and artificial intelligence, as well as war hero, Alan Turing's contributions were far ranging and path breaking. Turing is a giant on whose shoulders so many now stand."