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arXiv · 1505.03767

Thermodynamics of nonadditive systems

Ivan Latella·Agustín Pérez-Madrid·Alessandro Campa·Lapo Casetti·Stefano Ruffo
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Abstract

The usual formulation of thermodynamics is based on the additivity of macroscopic systems. However, there are numerous examples of macroscopic systems that are not additive, due to the long-range character of the interaction among the constituents. We present here an approach in which nonadditive systems can be described within a purely thermodynamics formalism. The basic concept is to consider a large ensemble of replicas of the system where the standard formulation of thermodynamics can be naturally applied and the properties of a single system can be consequently inferred. After presenting the approach, we show its implementation in systems where the interaction decays as $1/r^\alpha$ in the interparticle distance $r$, with $\alpha$ smaller than the embedding dimension $d$, and in the Thirring model for gravitational systems.

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Ivan Latella, Agustín Pérez-Madrid, Alessandro Campa, Lapo Casetti, Stefano Ruffo. 2015-05-14. Thermodynamics of nonadditive systems. https://doi.org/10.1103/physrevlett.114.230601

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