By Blake Brittain (Reuters) – A group of 11 nonfiction authors have joined a lawsuit in Manhattan federal court that accuses OpenAI and Microsoft of misusing books the authors have written to train the models behind OpenAI’s popular chatbot ChatGPT and other artificial-intelligence based software. The writers, including Pulitzer Prize winners Taylor Branch, Stacy Schiff and Kai Bird – who co-wrote the J. Robert Oppenheimer biography “American Prometheus” that was adapted into the hit film “Oppenheimer” this year – told the court on Tuesday that the companies infringed their copyrights by using…