At the close of the U.S. stock market on January 27, Nvidia's stock price plummeted 17%. In response, Nvidia said: "DeepSeek is an outstanding advance in artificial intelligence and an excellent example of test-time expansion. DeepSeek's research shows how to use this technology to create new models with the help of widely available models and computing power that fully complies with export control regulations. The reasoning process requires a large number of Nvidia GPUs and high-performance networks. Today we have three expansion laws: the pre-training and post-training laws that continue to apply, and the new test-time expansion law."