The UK has finally unveiled its Alan Turing bank note, and it's a fitting tribute to the pioneering computer scientist in both what it represents and the technology behind it. To start, the durable polymer £50 bill completes the Bank of England's "most secure" set of notes to date with anti-counterfeiting features appropriate for the legendary WWII codebreaker, including a metallic hologram as well as windows themed around Bletchley Park and a microchip.
The imagery is a nod to Turing's many achievements, including some deep cuts that you might not immediately recognize. The mathematical formula you see comes from Turing's influential 1936 paper "On Computable Numbers," a foundational work for computer science. You'll also see pictures of the Automatic Computing Engine Pilot Machine (the trial model for a very early computer) and schematics for the British Bombe codebreaking machine Turing specified. Ticker tape shows Turing's June 23rd, 1912 birth date in binary code, and there are nods to Turing's morphogenetic work through sunflower-like spiral features and foil.
The note will be issued on Turing's birthday. Its existence illustrates the importances of computer science and mathematics in modern society, as Turing's bill joins those featuring Winston Churchill (£5), Jane Austen (£10) and artist JMW Turner (£20). It also represents cultural progression — the UK government persecuted Turing for being gay despite his groundbreaking work, and now it's celebrating him as a champion of the LGBTQ community.