Irreversibility and quantum measurement—The observer’s role

William C. Schieve, Lawrence Paul Horwitz

Asher Peres

The Schr\"odinger equation cannot convert a pure state into a mixture (just as Newton's equations cannot display irreversibility). However, to observe phase relationships between macroscopically distinguishable states, one has to measure very peculiar operators. An example, constructed explicitly, shows that the classical analog of such an operator cannot be measured, because to do so would violate classical irreversibility. This result justifies von Neumann's measurement theory, without any hypothesis on the role of the observer.

CESAR ARELLANES

Measurement in quantum mechanics is commonly treated as a passive observational process that reveals properties of an underlying physical system. However, both theoretical analysis and experimental practice suggest that measurement interactions are physical events that irreversibly alter system states and their subsequent evolution. This work advances the hypothesis that measurement events function as generative interactions that actively produce realized states, rather than merely disclosing pre-existing conditions.Focusing on non-equilibrium dynamics, we examine the role of discrete interaction events in the transition from potential configurations to actualized states. Measurement interactions are characterized as localized, irreversible processes that introduce stable correlations and constrain future system evolution. From this perspective, state realization is associated with event-based commitments rather than continuous revelation, aligning naturally with thermodynamic irreversibility and entropy production.Preliminary conceptual analysis indicates that this generative role of measurement events is consistent with established formulations of quantum theory, including unitary evolution prior to measurement and the statistical structure of observed outcomes. The proposed viewpoint does not modify existing formalism or introduce new dynamical laws, but instead reframes the ontological role of measurement within standard theory.1Analogous event-driven state transitions appear across a range ofnon-equilibrium systems, including thermodynamic processes, information processing, chemical reactions, and distributed computational protocols. These analogies are noted to highlight structural commonalities in state actualization, rather than to assert cross-domain phys-ical equivalence.The present work introduces this hypothesis as a foundational perspective on the role of discrete interaction events in state formation. Broader structural implications and potential extensions of this framework are reserved for future investigation. Keywords: measurement theory, non-equilibrium dynamics, quantum observation, state formation, irreversibility

W. Ebeling

Stanley Everett Sambey

Traditional treatments of observation in physics implicitly privilege measurement as a prim-itive or consciousness-dependent act. This paper proposes a revised, non-anthropocentric Lawof Observation in which observation is defined as the irreversible formation of constraints withina dynamical system. Measurement is shown not to be fundamental, but to exist only withina bounded intermediate regime between full reversibility and full saturation. This frameworknaturally resolves the quantum measurement problem, clarifies the role of decoherence, and ex-plains the classical appearance of gravitational systems without modifying quantum dynamics.Numerical simulations of dissipative lattice fields demonstrate persistent constraint formation,memory without storage, and irreversibility in the absence of observers. Observation is thereforea physical condition, not an act.