Energy additivity as a requirement for universal quantum thermodynamical frameworks.

ABSTRACT: The quest to develop a general framework for thermodynamics, suitable for the regime of strong coupling and correlations between subsystems of an autonomous quantum "universe," has entailed diverging definitions for basic quantities, including internal energy. While most approaches focus solely on the system of interest, we propose that a universal notion of internal energy should also account for the environment in order to keep consistency with the closed-system energy of the universe. We introduce an abstract framework to describe all effective Hamiltonian-based approaches and address a rigorous definition of energy additivity in this context, in both a weak and a strong form, discussing the underlying subtleties. As an illustration, we study a particular two-qubit universe model, obtai

SUBMITTER: Neves LR 

PROVIDER: S-EPMC12474918 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature