Claude Fable 5.1 solved a 370-year-old cipher in forty-four minutes. This tracks with what I wrote about AIs doing mathematics: It’s good at things that involve lots of searching and testing. [...]

Really interesting piece of cryptographic history : In November 2023, a large cache of his wartime papers—nicknamed the “Bayley papers”—was auctioned in London for almost half a million U.S. dollars. The previously unknown cache contains many sheets in Turing’s own handwriting, telling of his top-secret “Delilah …

Researchers are using machine learning algorithms to decrypt historical pencil-and-paper ciphers. [...]

Sent by a Spanish diplomat. Apparently people have been working on it since it was rediscovered in 1860. [...]

Charles Bennett and Gilles Brassard have won the 2026 Turing Award for inventing quantum cryptography. I am incredibly pleased to see them get this recognition. I have always thought the technology to be fantastic, even though I think it’s largely unnecessary. I wrote up my thoughts back in …

Here’s a fun paper: “ The Naibbe cipher: a substitution cipher that encrypts Latin and Italian as Voynich Manuscript-like ciphertext “: Abstract: In this article, I investigate the hypothesis that the Voynich Manuscript (MS 408, Yale University Beinecke Library) is compatible with being a ciphertext by attempting to develop a …

The Business of Secrets: Adventures in Selling Encryption Around the World by Fred Kinch (May 24, 2004) From the vantage point of today, it’s surreal reading about the commercial cryptography business in the 1970s. Nobody knew anything. The manufacturers didn’t know whether the cryptography they sold was …

In the early 1960s, National Security Agency cryptanalyst and cryptanalysis instructor Lambros D. Callimahos coined the term “Stethoscope” to describe a diagnostic computer program used to unravel the internal structure of pre-computer ciphertexts. The term appears in the newly declassified September 1965 document Cryptanalytic Diagnosis with the Aid of …

Well, this is interesting: The auction, which will include other items related to cryptology, will be held Nov. 20. RR Auction, the company arranging the sale, estimates a winning bid between $300,000 and $500,000. Along with the original handwritten plain text of K4 and other papers related …

The NSA and GCHQ have jointly published a history of World War II SIGINT: “ Secret Messengers: Disseminating SIGINT in the Second World War.” This is the story of the British SLUs (Special Liaison Units) and the American SSOs (Special Security Officers). [...]

Interesting article —with photos!—of the US/UK “Combined Cipher Machine” from WWII. [...]