The AI boom has all 4 classic bubble signs — and it could pop in 2026 if interest rates rise, a top economist says

The current surge in artificial intelligence investments is raising alarms, as leading economist Ruchir Sharma indicates that it exhibits all the classic signs of a bubble. In a recent discussion with Nicolai Tangen, CEO of Norges Bank Investment Management, Sharma outlined his concerns regarding the sustainability of the AI boom and its potential repercussions by 2026. Sharma's analysis hinges on what he refers to as the 'four O's' of bubble identification: overinvestment, overvaluation, over-ownership, and over-leverage. According to him, the AI market is flashing warnings on all fronts. The massive influx of capital, particularly in the U.S., mirrors the patterns seen during previous economic bubbles, such as the dot-com era. He pointed out that the valuations of key AI companies are nearing bubble levels when assessed against long-term earnings and cash flow metrics. Moreover, American investors are currently holding an unprecedented portion of their wealth in equities, predominantly linked to AI. Big Tech firms like Meta, Amazon, and Microsoft have started accumulating substantial debt to support their AI initiatives, a behavior that Sharma identifies as a hallmark of a late-stage bubble. Sharma estimates that approximately 60% of U.S. economic growth this year has stemmed from AI investments, bolstered by both corporate spending on infrastructure and the wealth effect enhancing consumer spending among affluent households. However, he cautions that the broader economy appears fragile without this AI-driven momentum. He stated, "Outside of AI, there's a lot of weakness in the U.S. economy," highlighting the precarious nature of this investment landscape. While Sharma acknowledges the challenge of predicting the exact timing of a market correction, he emphasizes that rising interest rates are the primary catalyst that typically triggers a bubble burst. He identified three concerning trends: persistent inflation that remains above the Federal Reserve's target, the Fed's struggle to meet its inflation goals for five consecutive years, and the sustained growth of AI investments that could exacerbate inflation. Sharma asserts, "At the slightest sign that interest rates are going to go up, I think that's your sign that, 'Okay — this is done now.'" Rising rates would increase borrowing costs and diminish the valuations of high-growth companies, creating a precarious situation for investors. Looking ahead to 2026, Sharma's outlook resonates with other financial experts, who have varying predictions about the timing of a potential market correction. While some, like Greg Jensen from Bridgewater Associates, believe the bubble is still unfolding, others warn of significant turmoil in the coming decade. Despite the risks, Sharma suggests that the AI boom could ultimately yield positive outcomes, similar to past tech bubbles that fostered infrastructure growth. He believes quality stocks—companies with strong returns, solid balance sheets, and consistent earnings—may emerge as the best investment choice following any market correction.