Events in Physics
Professor Ian Ford, Stochastic Entropy Production, Irreversibility, and Rules for Demons
Thermodynamic entropy is uncertainty and its apparent production is brought about by the complex dynamics of the world when we fail to attend to all of its details. I'd like to describe the modern framework of stochastic thermodynamics that underpins this and provides a connection between dynamics and thermodynamics. I shall illustrate how the expectation value of stochastic entropy production can serve as a measure of the irreversibility of processes such as heat conduction. By investigating the mechanics of measurement and feedback, we'll also consider the attempts of Maxwell's demon to subvert the second law of thermodynamics. It is possible to imagine scenarios where thermodynamic entropy is actually reduced but it turns out that even demons have to abide by certain dynamical rules that protect the second law.