Entropy Growth During Free Expansion of an Ideal Gas

Explore the concept of entropy growth during free expansion of an ideal gas in this 44-minute conference talk by Abhishek Dhar at the Erwin Schrödinger International Institute for Mathematics and Physics. Delve into Boltzmann's construction of an entropy function for macroscopic system microstates, using the simple example of a one-dimensional gas of non-interacting point particles. Examine two specific macrostate constructions and understand how concepts like initial conditions, typicality, large numbers, and coarse-graining play crucial roles in observing macroscopic irreversibility and entropy increase. Discover why notions of ergodicity and chaos may be less relevant than commonly believed. Gain insights into the behavior of interacting gases and their entropy growth. This talk was presented as part of the Thematic Programme on "Large Deviations, Extremes and Anomalous Transport in Non-equilibrium Systems" at ESI in 2022.