The measurement problem in quantum mechanics: A phenomenological investigation

WU Guo-lin

While quantum mechanics has proven successful in its calculations and predictions, a debate persists regarding its understanding. This chapter considers the fundamental concepts of phenomenology and its connection to early quantum mechanics, including the exploration of quantum mechanics by F. London & E. Bauer using phenomenology. Phenomenological investigations of quantum mechanics in recent years have evolved. For instance, the informational interpretation of quantum mechanics, introduced by C. Rovelli in 1996 and advanced by Fuchs and C. M. Caves, offers a new perspective on quantum mechanics and possesses phenomenological tendencies which provide new insights into the problem of quantum measurement. Interestingly, phenomenology has its strong ties to hermeneutics. Therefore, this chapter sheds new light on quantum mechanics via hermeneutical analyses, and bridges the gap between the humanities and the natural sciences. In hermeneutics, interpretation encompasses two key aspects: Erklärung (Explanation) and Auslegung (Explication), where the former establishes clear and objective descriptions, similar to the “shuo ming” (说明) concept in Chinese, and the latter unveils deeper meanings and context, similar to the “chan shi” (阐释) concept in Chinese. The iterative process of explanation and explication plays a crucial role in the development of quantum mechanics. Hermeneutics allows us to view quantum matter with a new perspective, and new features are revealed such as “fusion of horizons” and “history of effects”, where the former is the merging of observer and observed realities in the context of quantum mechanics, while the latter means that the past, present, and future of a quantum system influence its overall reality. For this reason, the photon’s past, in the delayed-choice experiment, becomes an unfinished entity, a superposition waiting to be defined by measurement. This measurement collapses the possibilities and merges the photon’s past and present realities into a single, unified “whole”.

J. M. Jauch

Badis Ydri

John von Neumann

This chapter considers what would happen to a mixture with the statistical operator 𝗨 if a quantity 𝖱 with operator 𝖱 is measured in it. It then investigates the thermodynamics of quantum mechanical ensembles from two different points of view. First, the chapter assumes the validity of both of the fundamental laws of thermodynamics, and proceeds on this basis to calculation of the entropy of ensembles. In this effort the normal methods of phenomenological thermodynamics are applied, and quantum mechanics plays a role only insofar as these thermodynamic observations relate to objects whose behavior is regulated by the laws of quantum. Afterwards this chapter proves the validity of these fundamental laws in quantum mechanics. Next, the chapter introduces some reversibility and equilibrium problems. Finally, this chapter discusses the macroscopic measurement.

修三 小川

Boido, Mario

The quantum measurement problem has long been framed as a conflict between the continuous, unitary evolution of quantum systems and the discrete, definite events that appear in experience. This white paper argues that the problem arises not within physics, but at the interface between physical description and the temporal structure of consciousness. Quantum mechanics describes potentials—amplitudes, correlations, and evolving relations—but it contains no resources for generating events, definiteness, or a present moment. These belong to the phenomenology of experience. Drawing on the Phenomenology of the Human Experience of Time (PHET), I develop an account of how consciousness synthesizes retention (the just-past), presence (the unfolding now), and anticipation (the imminent future) into discrete events. On this view, “collapse” is not a physical process but the experiential actualization of a physical interaction. Classicality does not emerge from physics; it emerges from the temporal organization of consciousness. This framework dissolves the measurement problem, completes relational quantum mechanics, clarifies the appearance of classical definiteness, and reconciles quantum formalism with lived reality—all without modifying the physics. Events arise in experience, not in physical ontology.