Entropy and sign conventions

Abstract

It is a fundamental cornerstone of thermodynamics that entropy (\(S_{U,V}\)) increases in spontaneous processes in isolated systems (often called closed or thermally closed systems when the transfer of energy as work is considered to be negligible) and achieves a maximum when the system reaches equilibrium. But with a different sign convention entropy could just as well be said to decrease to a minimum in spontaneous constant U, V processes. It would then change in the same direction as the thermodynamic potentials in spontaneous processes. This article discusses but does not advocate such a change.