Quantum-State Scaling and Thermodynamic Irreversibility

We had previously shown [T. Yarman et al., Results Phys. 10 (2018) 818–821] that the classical adiabatic relation pV ^5/3=Constant for an ideal monatomic gas admits a direct quantum-mechanical formulation in terms of Planck’s constant and confinement-dependent quantum-state indices. This result suggests that macroscopic thermodynamic scaling laws reflect an underlying quantum-state structure. In the present work, we revisit this quantum-state scaling framework and discuss how it may provide a complementary language for thermodynamic accessibility and macroscopic irreversibility. In particular, we emphasize the conceptual distinction between microscopic reversibility, the arrow of time, and operational macroscopic irreversibility. Within this perspective, irreversibility may be interpreted in terms of asymmetries in accessible quantum-state configurations under changing confinement and energy conditions, while the underlying microscopic equations remain formally time-reversal symmetric. At the same time, the concept of operationally inaccessible microscopic quantum reconstruction, such as that with regards to fission, naturally emerges. Still, we do not claim to replace Boltzmannian, correlation-based, or information-theoretic approaches. Rather, the present study proposes a complementary quantum-state scaling perspective for discussing thermodynamic accessibility and the macroscopic evolution of complex systems. Even so, within the present framework, these practical limitations on thermodynamic accessibility do not necessitate a breakdown of formal microscopic reversibility; rather, they align with the Boltzmannian view that macroscopic reversals remain formally possible yet are rendered overwhelmingly inaccessible in practice.