Tech stocks surge as wave of interest in AI drives $4tn rally

Shares in some firms involved in AI technology more than double in value as traders bet on massive growth in industry

A rush of interest in artificial intelligence (AI) has helped to fuel a $4tn (£3.2tn) rally in technology stocks this year, with the US Nasdaq exchange reaching its highest level since last August in a week that saw the chipmaker Nvidia poised to become the next trillion-dollar company.

Some stocks seen as AI winners – such as semiconductor makers and software developers – have more than doubled in value as traders bet on massive growth in the industry, even as fears mount over waves of job losses as everyday tasks become automated.