Entropy of continuous mixtures and the measure problem

P. Maynar; E. Trizac

doi:10.1103/physrevlett.106.160603

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arXiv · 1104.4914

Entropy of continuous mixtures and the measure problem

P. Maynar·E. Trizac

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Abstract

In its continuous version, the entropy functional measuring the information content of a given probability density may be plagued by a "measure" problem that results from improper weighting of phase space. This issue is addressed considering a generic collision process whereby a large number of particles/agents randomly and repeatedly interact in pairs, with prescribed conservation law(s). We find a sufficient condition under which the stationary single particle distribution function maximizes an entropy-like functional, that is free of the measure problem. This condition amounts to a factorization property of the Jacobian associated to the binary collision law, from which the proper weighting of phase space directly follows.

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P. Maynar, E. Trizac. 2011-04-26. Entropy of continuous mixtures and the measure problem. https://doi.org/10.1103/physrevlett.106.160603

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