An engineer has utilized AI to break a previously unsolved cipher used by Napoleon Bonaparte to send secret messages to his generals — enabling us to read a 217-year-old letter for the first time. The announcement has historians excited about AI's potential to become a modern-day "Rosetta Stone" for translating coded historical messages. Carter Church, an AI engineer at cybersecurity firm Sentinel One, laid out the findings in a post on X on Wednesday (Sept. 30), explaining how he gave OpenAI's new model GPT-6 Astra one prompt and one image to crack the centuries-old code. Six hours later, the task was complete."I didn't believe it at first," Church told Live Science in a message. "Everyone ...