Problems of nonextensivity in hadron thermodynamics

Hadron thermodynamics deals with a gas of indistinguishable particles whose mass spectrum is taken to have the formKm^ae^bm. A long-standing inconsistency is pointed out, namely the nonextensive nature of the entropy found in some treatments by way of the microcanonical ensemble, which contrasts with the extensive nature found by way of the canonical ensemble. The former result is due to an error. After correction, the two ensembles are found to lead to the same expressions for the thermodynamic quantities ifa –7/2. Some of these expressions are new. Fora<–5/2, the microcanonical approach is used to examine a model in which one particle is appreciably heavier than the rest. However, the resulting entropy is found to be unphysical.