The Nernst theorem and heat capacities of thermodynamic systems at ultra-low temperatures

Abstract

The multitudinous expressions of the heat capacity possibly and impossibly appearing in ultra-low temperature thermodynamic systems are determined by using the Nernst theorem. It is found that the expression of the heat capacity possibly appearing in ultra-low temperature systems must satisfy Nernst’s theorem. Crucially, control discrimination methods are presented mathematically through which it can be judged for one new expression of the heat capacity that it possibly appears in ultra-low temperature thermodynamic systems or is fictional. These findings will contribute to enhancing our understanding of the behavior of ultra-low temperature systems.