Alan Turing’s lost notebook
Alan Turing’s personal mathematical notebook went on display a few days ago at Bletchley Park near London, the European headquarters of the Allied codebreaking operation in World War II. Until now, the notebook has been seen by few — not even scholars specializing in Turing’s work. It is on loan from its current owner, who acquired it in 2015 at a New York auction for over one million dollars.