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Dual description of nonextensive ensembles

Jan Naudts
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Abstract

In the case of a system with an unbounded hamiltonian the entropic index q of non-extensive thermodynamics has an upperbound q_c>1 beyond which the formalism becomes meaningless. The expression 1/(q_c-1) is the dimension of the state space (i.e. the manifold of density matrices) in the context of non-commutative geometry. For q=q_c an ultraviolet cutoff E< E_ub is needed to guarantee the existence of the equilibrium density matrix. Duality between q>1 and q<1-statistics via a q --> 1/q transformation is established. It leads to an overall picture in which the meaning of both q>1-statistics and q<1-statistics is clarified.

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Jan Naudts. 1999-04-13. Dual description of nonextensive ensembles. https://arxiv.org/abs/cond-mat/9904070

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