Shares in AI darling Nvidia popped in premarket trade after the U.S. firm beat expectations in third-quarter results after the closing bell on Wednesday. Shares were last trading 5.5% higher at 4:15 a.m. ET. Nvidia topped forecasts for revenue, which jumped 62% to $57.01 billion year-on-year, and issued stronger-than-expected fourth-quarter sales guidance. "There's been a lot of talk about an AI bubble," Nvidia CEO Jensen Huang told investors on an earnings call, as the firm set out its view of