AI bubble fears return as Wall Street falls back from short-lived rally

Fears of a growing bubble around the artificial intelligence frenzy resurfaced on Thursday as leading US stock markets fell, less than 24 hours after strong results from chipmaker Nvidia sparked a rally. Wall Street initially rose after Nvidia, the world's largest public company, reassured investors of strong demand for its advanced data center chips. But the relief dissipated, and technology stocks at the heart of the AI boom came under pressure. The benchmark S&P 500 closed down 1.6%, and the Dow Jones industrial average closed down 0.8% in New York. The tech-focused Nasdaq Composite closed down 2.2%.