Status of the Clausius inequality in classical thermodynamics

Abstract

We present an analysis of the foundations of the well known Clausius inequality. It is shown that, strictly speaking, the inequality is not a logical consequence of the Kelvin-Planck formulation of the second law of thermodynamics. Some thought experiments demonstrating the violation of the Clausius inequality are considered. Also, a reformulation of the Landauer's principle in terms of the Clausius inequality is proposed. This version of the inequality may be considered a consequence of the fluctuation theorem.