From Nature’s Tendency To Statistical Mechanics

An Account of Thermodynamic Entropy ◽

10.2174/9781681083933117010010 ◽

2017 ◽

pp. 56-60

Author(s):

Alberto Gianinetti

Keyword(s):

Statistical Mechanics ◽

Macroscopic Level

Some processes happen spontaneously. What, at a macroscopic level, appears as a nature’s tendency, is an effect of the complex statistical behaviour of the microscopic particles: their overall net effect emerges at the macroscopic level as a spontaneous force that determines if and how a system can spontaneously change, and if and toward which direction a process is therefore started.

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Boltzmann Entropy & Equilibrium in Non-Isolated Systems

An Account of Thermodynamic Entropy ◽

10.2174/9781681083933117010012 ◽

2017 ◽

pp. 74-92 ◽

Cited By ~ 1

Author(s):

Alberto Gianinetti

Keyword(s):

Statistical Mechanics ◽

Stable Condition ◽

Microscopic Level ◽

Boltzmann Entropy ◽

Microscopic Approach ◽

Macroscopic Level ◽

Probable Distribution ◽

Isolated Systems ◽

Most Probable Distribution

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.

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Entropy in Statistical Mechanics

An Account of Thermodynamic Entropy ◽

10.2174/9781681083933117010008 ◽

2017 ◽

pp. 41-49

Author(s):

Alberto Gianinetti

Keyword(s):

Statistical Mechanics ◽

Macroscopic Level ◽

Microscopic World

The systems we can directly see are composed of huge numbers of particles. So, the properties of these systems are obtained as statistical averages of the effects of their particles. This casts a conceptual bridge between the macroscopic world wherein we observe systems with their overall properties and the microscopic world where particles with their own properties dominate the scene. Statistical mechanics shows that the former world is determined by what happens in the latter, and this approach provides a better, finer understanding of what’s going on at the macroscopic level and why.

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