Dow closes down 500 points on AI bubble fears

Stocks closed markedly lower on Tuesday as fears of a bubble in artificial intelligence technology hammered markets for a fourth consecutive trading day. The Dow Jones Industrial Average dropped 498 points, or 1%, while the S & P 500 fell 0.8%. The tech-heavy Nasdaq tumbled 1.2%. The selloff, which has touched some of the world's largest companies, marks a rare bout of turbulence on this year’s glide path to higher returns. In recent days, many investors have raised alarms about tech companies dependent on AI. As big-tech names spend hundreds of billions to build data centers necessary to run the energy-intensive technology, the financial benefits remain uncertain. "Tech companies have to spend to keep up with surging demand, but that demand largely hasn’t turned into profits or productivi