Boltzmann Entropy & Equilibrium in Non-Isolated Systems
Pp. 74-92 (19)
The microscopic approach of statistical mechanics has developed a series of
formal expressions that, depending on the different features of the system and/or
process involved, allow for calculating the value of entropy from the microscopic state
of the system. This value is maximal when the particles attain the most probable
distribution through space and the most equilibrated sharing of energy between them.
At the macroscopic level, this means that the system is at equilibrium, a stable
condition wherein no net statistical force emerges from the overall behaviour of the
particles. If no force is available then no work can be done and the system is inert. This
provides the bridge between the probabilistic equilibration that occurs at the
microscopic level and the classical observation that, at a macroscopic level, a system is
at equilibrium when no work can be done by it.
Approximate equiprobability, Approximate isoenergeticity,
Boltzmann entropy, Boltzmann factor, Canonical ensemble, Canonical partition
function, Dominating configuration, Energetic (im)probability, Equal
probabilities, Equilibrium fluctuations, Fundamental thermodynamic potential,
Gibbs free energy, Grand canonical ensemble, Helmholtz free energy,
Maximization of entropy, Microcanonical partition function, Microcanonical
system, Minimization of energy, Temperature, Thermostatic bath.
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