Changes occur constantly in nature, but there is a type of change that is particularly fascinating. Consider a magnet, at a very high temperature the spins are randomized and there is no magnetization, but if we decrease the temperature beyond a so-called “critical point” the spins will start pointing in the same direction (like in the image above), producing magnetization, even if there is no external field or anything telling the spins where to point.

 

This is an example of critical transitions which occur when very small perturbations spread through the system leading into global coordination. Striking similarities between critical transitions in physics and other changes observed in biological and social sciences led to the construction of an enormous number of idealized models that export the physics of criticality to a variety of domains, from bird flocking to market crashes, opinion polarization and even ecological collapse. But can we really use physics to understand why birds fly in the way they do or why people decide to suddenly change their opinions? MACBeh will shed crucial light on these questions by revealing the limits and strengths of the export of the physics of criticality to other domains.