诺贝尔经济学奖得主迈克尔·斯宾塞：美股市值集中度前所未见，AI投资潮存在一些泡沫

Core Insights - The U.S. stock market is experiencing a frenzy driven by enthusiasm for artificial intelligence investments [1] - Major companies are heavily investing in AI models, research, quantum computing, and data center construction, leading to increased demand for electricity [1] - There are indications of market bubbles due to concentrated investments in technology [1] Investment Trends - Companies are increasing investments in AI and related technologies due to fears of falling behind in strategic competition [1] - The concentration of market value is notable, with over 30% of the S&P 500 index's market capitalization held by the top seven technology companies, a level of concentration described as "almost unprecedented" [1] Economic Concerns - The U.S. faces unsustainable sovereign debt levels, with unclear solutions to address this issue [1] - Despite strong economic growth, the recent depreciation of the dollar may reflect foreign investors' concerns about accumulating risks in the U.S. financial sector [1]