Rethinking Boltzmannian Equilibrium. Issue 5 (December 2015)

• Record Type: Journal Article
• Authors: Werndl, Charlotte; Frigg, Roman
• Is Part Of: Philosophy of science. Volume 82:Issue 5(2015)
• Page Start: 1224
• Page End: 1235
• Publication Date: 2015-12
• Subjects: Science -- Periodicals; Science -- Philosophy; Science; Science -- Philosophy; Philosophie des sciences; Epistemology; Periodicals; 501
• DOI: 10.1086/683649
• Languages: English
• ISSNs: 1539-767X

Abstract

Abstract : Boltzmannian statistical mechanics partitions the phase space of a system into macroregions, and the largest of these is identified with equilibrium. What justifies this identification? Common answers focus on Boltzmann's combinatorial argument, the Maxwell-Boltzmann distribution, and maximum entropy considerations. We argue that they fail and present a new answer. We characterize equilibrium as the macrostate in which a system spends most of its time and prove a new theorem establishing that equilibrium thus defined corresponds to the largest macroregion. Our derivation is completely general and does not rely on assumptions about the dynamics or interparticle interactions.