AB A.I. advances by Chinese upstarts rattled U.S. markets yesterday, wiping hundreds of billions of dollars from the leading tech indexes. Falling tech stocks also dented market indexes in Europe and Japan, and the dollar slipped against the currencies of major U.S. trading partners. The slide came days after the Chinese A.I. company DeepSeek said it could match the abilities of cutting-edge chatbots while using a fraction of the specialized computer chips that leading A.I. companies rely on. The news prompted investors to rethink the valuations of companies like Nvidia, whose equipment powers the most advanced A.I. systems. The overall tech sector of the S&P 500 has had a rocky start to the year, losing about 4 percent of its value, while every other major sector has gained over the same period. Because of the tech industry’s size and influence, this has weighed on the S&P 500 index, which is up about 2 percent for the year. - The New York Times
