Probabilistic properties of nonextensive thermodynamic

Based on the Tsallis entropy, the nonextensive thermodynamic properties are studied as a qdeformation of classical statistical results using only probabilistic methods and straightforward calculations. It is shown that the constant in the Tsallis entropy depends on the deformation parameter and must be redefined to recover the usual thermodynamic relations. The notions of variance and covariance are generalised. A partial derivative formula of the entropy is established. It verifies important relations from which most of the nonextensive thermodynamics relations can be recovered. This leads to a new proof of a highly nontrivial conclusion that thermodynamic relations and Maxwell relations in non extensive thermodynamic have the same forms as those in ordinary nonextensive statistical mechanics. Theoretical results are applied to ideal gas. The case of fermions and bosons systems with fractal distributions is also considered. PACS : 05.20.-y, 05.70.-a, 05.30.-d.