From my favourite magazine this week

Gibbs entropy and dynamics

G. Piftankin and D. Treschev
Let M be the phase space of a physical system. The dynamics
is determined by the map T : M-->M, preserving the measure
[mu]. Let nu be another measure on M, dnu=rho d[mu]. Gibbs
introduced the quantity s(rho)=[integral]rho log rho d[mu]
as an analog of the thermodynamical entropy. Attempts to
... [Chaos 18, 023116 (2008)] published Tue May 20, 2008.

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