Erwin Schrödinger is best known to non-scientists for his thought experiment involving a cat (or maybe his unconventional living arrangement), but he also wrote What is Life?, a book that attempted to bring the fields of physics and biology closer to each other. Today, experiment is beginning to reach the point where we can see if the specifically quantum aspects of physics play a direct role in biology. Even though in a fundamental sense, everything is quantum mechanical, the quantum state—the entity that encodes the probability of the outcomes of various interactions—doesn’t usually need to be considered for biology. However, it’s still possible life has learned to harness quantum effects, ranging from tunneling to entanglement, to gain an evolutionary advantage.

An intriguing aspect of all of these possibilities is that perhaps evolution has figured out a better way of performing tricky quantum manipulations than we have. In a sense, that’s not surprising: life has had a long time to evolve photosynthesis, photoreception, and navigation, while our understanding of quantum mechanics just began in the 1920s and ’30s. [Read more…]