A classification of nonequilibrium steady states based on temperature correlations

Although generalized ensembles have now been in use statistical mechanics for decades, including frameworks such as Tsallis' nonextensive statistics and superstatistics, a classification of these outlining the boundaries validity different families models, is still lacking. In this work, proposed terms supercanonical subcanonical ensembles, according to newly defined parameter, inverse temperature covariance parameter $\mathcal{U}$. This non-negative superstatistics (and equal variance temperature) but can be negative other adquiring then broader meaning. It shown that $\mathcal{U}$ every region composite system steady state, examples are given states.