More Is Still Different

2022 marked the 50^th anniversary of Philip Anderson’s classic article ``More is Different,’’ a deep analysis which asked what it means for different parts of science to be “fundamental.” Though Anderson’s insights into physics remain relevant to this day, my talk will focus instead on the argument that questions about whether microscopic understanding is the route to “fundamental” understanding are even more important in the context of modern biology. The molecular conception of biology has been one of the biggest success stories in the history of science. And yet, with the proliferation of sequences and protein and RNA structures, questions abound about the implications of such data for interpreting biological reality. In this talk, after a brief review of Anderson’s classic paper, I will give several disparate examples of the way that “natural variables,” coarse-grained descriptions of diverse biological phenomena emerge that provide both intuition and predictive power. The specific examples will consider a billion-fold difference in length scales ranging from the herding of wildebeest to the actin-based motility of parasites to the dynamics of inducible transcription factors. These examples will reveal emergence as illustrated by herding without animals, cytoskeletal dynamics without actin and molecular dynamics without molecules.