One of the perks of being a Maths Scholar is the events organised throughout the year. This event, my first, was a visit to Bletchley Park, Britain's main decryption establishment during World War Two. As you’d expect for a codebreaking site, there was plenty of mystery and intrigue, starting with the joining instructions: meet your contact at the main entrance. You’ll know them from the secret sign which was … an inflatable Nemo (as in “Finding Nemo”), of course. A bit more “Johnny English” than “James Bond” but it did the trick!
Inside, the main exhibition was really informative, explaining the history of the site and how it operated during WW2. There were genuine Enigma machines and the Typex machines used by the British for encryption and decryption. On the interactive displays you could try your hand at tuning in to enemy radio signals and decrypting them.
During the lecture for Maths Scholars we learnt about modulo 2 arithmetic and how it applies to Vernam cyphers which were the basis for the Lorenz cypher machines used by the German High Command – an even more complex encryption system than Enigma. This links nicely to binary numbers and could easily be the basis of a classroom activity.
Next, we got right up-to-date with an introduction and explanation of how RSA encryption works. RSA is one of the first public key encryption systems which we use extensively for security on the internet. The maths behind this relies on factorizing the product of very large prime numbers and it was fascinating to see how this works. This makes for a great example to use in class of how maths is relevant in real life.
After the lecture there was time to join a guided tour round the site. The Bletchley Park guides were excellent, with loads of stories about the site during the war and the ground breaking work done there. Later, there was time to explore the site independently, from the original manor house to the numerous huts added later to accommodate the rapidly growing workforce. There’s even a replica of Alan Turing’s office in Hut 8, complete with mug chained to the radiator but I’m not sure if that was to stop it being stolen or just to stop him misplacing it.
All in all, a great day out and packed with real world applications of maths. I can’t wait for the next event.
By David Gee