5. Conclusion

The traditional answers to what the second principle of thermodynamics is are well known. The one based on the collapse postulate on the wave function according to von Neumann, which can in fact be seen as a black box for irreversible thermodynamic interaction in a classical environment, sees the second principle as emerging from QM. Within the orthodox QM framework, quantum measurement theory developed with the aim of rationalizing the interpretation of a sudden collapse by a smoother differentiable dynamical evolution. This led to the development of quantum open systems theory and typicality. Both of these so-called quantum thermodynamic approaches are firmly based on the orthodox belief that QM unitary reversible dynamics for any system is a foundation. Alternatively, a somewhat unorthodox approach, such as IQT, considers the possibility that the second principle is fundamental and non-emergent,...