Speaker: Gil Ariel, Associate Professor, Department of Mathematics, Bar Ilan
Title: Inferring entropy from structure
The thermodynamic definition of entropy can be extended to nonequilibrium systems based on its relation to information. To apply this definition in practice requires access to the physical system’s microstates, which may be prohibitively inefficient to sample or difficult to obtain experimentally. It is beneficial, therefore, to relate the entropy to other integrated properties which are accessible out of equilibrium. We focus on correlation functions and derive the information gained by a given measurement. In other words, any measured correlation function provides an upper bound for the entropy of an otherwise unknown system. We demonstrate our method in identifying phase transitions in simplified models of collective motion and experiments with swarming bacteria.
Joint work with Haim Diamant and Benjamin Sorkin.