Second Law and Non-Equilibrium Entropy of Schottky Systems -- Doubts and Verification

TL;DR

This paper critically examines the concept of non-equilibrium entropy in Schottky systems, questioning its validity and proposing a framework to derive thermodynamic inequalities without relying on non-equilibrium entropy as a primitive concept.

Contribution

It offers a new perspective by deriving Clausius inequality using contact temperature and non-equilibrium molar entropy, challenging traditional notions of non-equilibrium entropy.

Findings

Non-equilibrium entropy cannot be treated as a primitive concept.

Clausius inequality can be derived without non-equilibrium entropy.

Contact temperature and non-equilibrium molar entropy effectively describe system-environment interactions.

Abstract

Meixner's historical remark in 1969 "... it can be shown that the concept of entropy in the absence of equilibrium is in fact not only questionable but that it cannot even be defined...." is investigated from today's insight. Several statements --such as the three laws of phenomenological thermodynamics, the embedding theorem and the adiabatical uniqueness-- are used to get rid of non-equilibrium entropy as a primitive concept. In this framework, Clausius inequality of open systems can be derived by use of the defining inequalities which establish the non-equilibrium quantities contact temperature and non-equilibrium molar entropy which allow to describe the interaction between the Schottky system and its controlling equilibrium environment.