This excerpt from "Life on the Edge" explores the quantum mechanics involved in photosynthesis. It begins by introducing the question of how trees create their substance from air and light, referencing Richard Feynman and MIT's contributions to science. The text then examines the two-slit experiment to illustrate the wave-particle duality of quantum mechanics. It discusses quantum coherence and decoherence, explaining how these processes relate to photosynthesis. Finally, it looks at the role of chlorophyll and excitons in capturing and transferring solar energy, highlighting the efficiency of this quantum process. The text suggests that quantum mechanics plays a crucial role in photosynthesis and other natural processes.