FRANKFURT, April 21 : German central bank chief Joachim Nagel called on Tuesday for all institutions to have access to Anthropic's artificial intelligence model Mythos to keep the playing field even and to avoid it being misused.  The Bundesbank head said banking authorities must act to prevent the misuse of Anthropic's most advanced AI model to date, as it opens the door to new and sophisticated cyber risks. "Mythos is an AI model that appears capable of quickly identifying and exploiting