Divergent Warmth is an exploratory descent to a divergent boundary. The deep submergence vehicle Alvin frequently dives along the East Pacific Rise, where the seafloor is ripping apart along a seam. Despite the immense pressure several kilometers deep, creatures live on energy biosynthesized from the interplay of heat and chemical elements. Experimental research about life and the surfaces it thrives on is an ongoing practice here. Divergent Warmth is both an illustration of life and the conduct of science, and a reflection on the process of understanding complex systems.