What is the second law of thermodynamics and are there any limits to its validity?

TL;DR

This paper explores the fundamental nature of the second law of thermodynamics, proposing two comprehensive expositions that challenge traditional statistical mechanics interpretations and apply universally across all systems and states.

Contribution

It introduces two new expositions of thermodynamics that are revolutionary and universally applicable, questioning the conventional statistical mechanics view of entropy.

Findings

Proposes a universal framework for thermodynamics applicable to all systems and states.

Challenges the statistical mechanics interpretation of entropy as nonphysical.

Provides alternative perspectives on the second law's validity and scope.

Abstract

In the scientific and engineering literature, the second law of thermodynamics is expressed in terms of the behavior of entropy in reversible and irreversible processes. According to the prevailing statistical mechanics interpretation the entropy is viewed as a nonphysical statistical attribute, a measure of either disorder in a system, or lack of information about the system, or erasure of information collected about the system, and a plethora of analytic expressions are proposed for the various measures. In this paper, we present two expositions of thermodynamics (both 'revolutionary' in the sense of Thomas Kuhn with respect to conventional statistical mechanics and traditional expositions of thermodynamics) that apply to all systems (both macroscopic and microscopic, including single particle or single spin systems), and to all states (thermodynamic or stable equilibrium, nonequilibrium, and other states).