Abstract
Living cells need to organize chemical reactions.  In school, we learned that cells compartmentalize biochemistry using lipid bilayers.  However, many functional domains don’t have a membrane and appear to be held together by liquid-like cohesion. These ‘biomolecular condensates’ are thought to form by liquid-liquid phase separation, a phase transition analogous to spontaneous magnetization.

I’ll show some examples of how these phase transitions manifest in cells, and discuss in vitro experiments with model systems to probe their underlying physics.  I will emphasize the multifaceted role of thermodynamic critical points, which not only drive large-scale fluctuations, but also collaborate with biochemical activity to create stunning emergent ‘behaviors’.