A remark on Cauchy-elasticity

In the context of an essentially classical formulation of continuum thermodynamics, it is shown that “Part I” of the Second Law of Thermodynamics-which leads directly to the construction of the entropy function for a thermoelastic material-implies that stress is derivable from a potential function. By specializing the thermodynamical theory to obtain the mechanical theory, one can argue that all Cauchy-elastic materials must be Green-elastic. A natural imbedding of the set of Green-elastic materials in the set of thermoelastic materials is also provided.