Zipf law (which is a power law) is the maximum entropy distribution of a system of P particles in N boxes where P>>N. Its derivation is based on microcanonical ensemble in which the entropy is calculated for an isolated system. In the canonical ensemble the system is with contact with an external bath having a fix temperature T. The macroscopic quantities of the canonical ensemble are calculated from its partition function in which the probabilities decay exponentially with energy.
The question is: how is Zipf law a power law which can be obtained from exponential partition function?
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