A comment on a formulation of the second law of thermodynamics (Q1819583)

''There is no dynamical isolated process whose initial and final states coincide.'' This version of the second law of thermodynamics (principle) was proposed, in 1906, by Perrin. On the basis of linear one-dimensional and inhomogeneous thermoelasticity the author of the paper examines this principle. He states that the principle is indeed satisfied if the constitutive relations of the thermoelastic body satisfy a restriction that the second law is commonly thought to imply. On the other hand, the principle is strictly weaker than the second law.