For decades, software ate the world. Venture investors chased companies that could grow without factories, supply chains, or machines. Hardware was almost a dirty word. But now, Silicon Valley is getting physical . As the software boom cools and AI moves from chatbots into the physical world, investors are piling into robotics and so-called "physical AI," a term popularized by Nvidia CEO Jensen Huang to describe AI systems that can act in the real world. The pitch is that if AI transformed what