The Download: fetal brain surgery, and a White House AI summit

This sentence was written by an AI--or was it? OpenAI's chatbot, ChatGPT, presents us with a problem: How will we know whether what we read online is written by a human or a machine? Since it was released in November 2022, ChatGPT has been used by over a million people. It has the AI community enthralled, and it is clear the internet is increasingly being flooded with AI-generated text. We're in desperate need of ways to differentiate between human- and AI-written text in order to counter potential misuses of the technology.