高盛反击AI泡沫论调：美国科技股强劲涨势由基本面驱动

Core Viewpoint - Goldman Sachs analysis team indicates that while there are signs of a bubble in the current U.S. stock market, particularly with the strong performance of tech stocks, the ongoing rally is primarily driven by fundamental growth rather than irrational speculation [1][2] Group 1: Market Conditions - The report highlights that despite concerns about a potential bubble due to the ongoing bull market and rising tech stocks, there are significant differences compared to past periods of excessive speculation [1] - Current investor behavior and market pricing exhibit some characteristics similar to previous bubbles, including rising absolute valuation levels, increased market concentration, and heightened capital intensity among leading firms [1] Group 2: Company Performance - Leading companies that have seen the largest price increases generally possess exceptionally strong balance sheets, contrasting with typical bubble markets where many unprofitable new entrants dominate [1] - The AI sector is currently led by a few established giants rather than a large number of unprofitable newcomers, which is a hallmark of typical bubble conditions [1] Group 3: Valuation Insights - Although valuations in the tech sector have become relatively tight, they have not yet reached the levels seen during historical stock market bubbles [1] - The report notes that bubbles typically occur when both stock prices and valuations soar, leading to a total market capitalization that exceeds the potential future cash flows of related companies [1] Group 4: Investment Strategy - Goldman Sachs concludes that while the market does not appear to be in a bubble, the high market concentration and increasing competition in the AI sector suggest that investors should continue to focus on portfolio diversification [2]