Groups, nonadditive entropy and phase transitions

  title={Groups, nonadditive entropy and phase transitions},
  author={Nikos Kalogeropoulos},
  journal={International Journal of Modern Physics B},
We investigate the possibility of discrete groups furnishing a kinematic framework for systems whose thermodynamic behavior may be given by nonadditive entropies. Relying on the well-known result of the growth rate of balls of nilpotent groups, we see that maintaining extensivity of the entropy of a nilpotent group requires using a non-Boltzmann/Gibbs/Shannon (BGS) entropic form. We use the Tsallis entropy as an indicative alternative. Using basic results from hyperbolic and random groups, we… 
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