# Entropy growth during free expansion of an ideal gas

@inproceedings{Chakraborti2021EntropyGD, title={Entropy growth during free expansion of an ideal gas}, author={Subhadip Chakraborti and Abhishek Dhar and Sheldon Goldstein and Anupam Kundu and Joel L Lebowitz}, year={2021} }

To illustrate Boltzmann’s construction of an entropy function that is defined for a single microstate of a system, we present here the simple example of the free expansion of a one dimensional gas of hard point particles. The construction requires one to define macrostates, corresponding to macroscopic observables. We discuss two different choices, both of which yield the thermodynamic entropy when the gas is in equilibrium. We show that during the free expansion process, both the entropies… Expand

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