利空突袭，全线大跌！

Core Viewpoint - The article discusses the recent downturn in the U.S. stock market, particularly focusing on technology stocks, driven by concerns over high valuations, economic uncertainty, and the Federal Reserve's interest rate policies [3][5][8]. Group 1: Market Performance - U.S. major indices experienced a collective decline, with the Dow Jones and Nasdaq dropping over 1%, and the S&P 500 falling by 0.83% [3][4]. - The technology sector faced significant losses, with the "seven giants" of tech down nearly 2% and the Philadelphia Semiconductor Index down 2.3% [3][4]. - Individual stocks such as Nvidia, Micron Technology, and Amazon saw declines of nearly 3%, over 5%, and over 4% respectively [3][4]. Group 2: Investor Sentiment - Analysts attribute the sell-off in tech stocks to multiple factors, including persistent concerns over inflated AI valuations and a cooling expectation for Federal Reserve interest rate cuts [5][6]. - A recent Bank of America survey indicated that investor cash allocation has dropped below a critical threshold, triggering a "sell signal" for stocks [8][9]. - The survey revealed that 45% of respondents view a potential AI bubble as the biggest tail risk, with 53% believing AI stocks are already in a bubble [9]. Group 3: Economic Outlook - Investors are reassessing economic growth prospects, which is putting broader pressure on financial markets [6]. - Concerns about the Federal Reserve not implementing a third rate cut in December are increasing, contributing to ongoing pressure on risk assets [6][7]. - The anticipated capital expenditures by major tech companies for AI infrastructure are projected to reach $371 billion this year, with a total need of $5.2 trillion by the end of the decade [6].