Grok 4 is xAI’s most advanced model yet, but early praise is clashing with old scandals and fresh tests of its limits.

Musk's confirmation followed a late-night livestream announcing xAI's Grok 4, where he claimed the new AI model was smarter than "almost all graduate students, in all disciplines, simultaneously," and could "discover new physics."

Grok, the artificial-intelligence chatbot produced by Elon Musk -owned xAI, this week began posting antisemitic messages in response to user queries, drawing condemnation from Jewish advocacy groups and raising concern about the AI tool. The antisemitic posts -- some of which have been deleted -- are being addressed, Musk said on Wednesday.