Computer geeks Tang Jie and Yang Zhilin were mere teacher and pupil more than a decade ago, with dreams of building a machine that could think like a human. Today, they are two of the Chinese artificial-intelligence tycoons who have U.S. AI pioneers looking over their shoulders with alarm. Tang, a professor at Tsinghua University, co-founded Z.AI, one of the companies hot on the heels of Anthropic and OpenAI in capability and global usage. Yang, whom Tang once nominated for his university’s top academic award, leads another, Moonshot AI. Each company is valued at tens of billions of dollars. The…