This manuscript is a philosophical exploration grounded in established results from quantum decoherence theory. It does not propose a new physical theory, but examines whether determinism and existential meaning can be reconciled through a distinction between global quantum structures and local conditional experience.
This paper develops a theoretical framework in which existential experience emerges continuously from global quantum dynamics through the mediation of local observation. Within this framework, existentialism is reinterpreted as an effective experiential theory describing global determinism under conditions of local observation, rather than as an independent theoretical framework in competition with determinism. Consequently, once a continuous theoretical connection between determinism and existentialism has been established, the existence of free will is no longer a necessary precondition for evaluating their relationship. Free will remains open as an independent metaphysical problem, but its theoretical status is reconfigured from a foundational explanatory prerequisite to an independent object of philosophical inquiry.
On the basis of quantum-mechanical realism and the philosophical view that “determinism and indeterminism are mutually dual and symbiotically coexisting,” philosophical and physical perspectives are integrated to propose the “constraint–uncertainty” hypothesis in this paper. Combined with a temporal ontology of “a determined history and an open future,” a unified interpretative framework for quantum phenomena is established. First, in conjunction with experimental results on fullerene quantum interference and spin decoherence in diamond NV centers, the core hypothesis is proposed: when a system is subject to a single dominant constraint, its behavior exhibits deterministic characteristics and uncertainty is suppressed; when subject to multiple competing constraints, its behavior becomes indeterministic and determinism is weakened. It is further clarified that the “constraint” in this work refers to a physically real underlying dynamical mechanism. Second, based on this hypothesis and temporal ontology, a self-consistent interpretation is provided for quantum phenomena such as wave-function superposition and quantum entanglement. It is argued that the “constraint–uncertainty” hypothesis offers an ontological basis for the Heisenberg uncertainty principle, thereby correcting the imprecise characterization in mainstream quantum theory that reduces uncertainty to an intrinsic property of particles. This paper further explores the tension between quantum mechanics and general relativity, suggesting that they correspond to different physical regimes governed by distinct constraint structures. A complete constraint-based model should naturally incorporate gravity, potentially offering a new perspective for the unification of the two theories. This paper further elaborates on the issues concerning temporal ontology. The author holds that variability serves as the meta-setting of physics, and the irreversibility of time is essentially a combination of variability and uncertainty, which also gives rise to the openness of the future. The uniqueness of the subject’s existential position determines the definiteness of history.
Abstract Quantum decoherence is receiving a great deal of attention today not only in theoretical and experimental physics but also in branches of science as diverse as molecular biology, biochemistry, and even neuropsychology. It is no surprise that it is also beginning to appear in various philosophical debates concerning the fundamental structure of the world. The purpose of this article is primarily to acquaint non‐specialists with quantum decoherence and clarify related concepts, and secondly to sketch its possible implications – independent of particular interpretations of quantum mechanics – for broader philosophical debates. For example, decoherence shows that any method of parsing nature into levels or parts cannot be in principle but instead derives from our perception of the world as classical, a perception that is itself sustained by the process of decoherence.
We look into the ontology of quantum theory as distinct from that of the classical theory in the sciences, following a broadly Kantian tradition and distinguishing between the noumenal and phenomenal realities where the former is independent of our perception while the latter is assembled from the former by means of fragmentary bits of interpretation. Within this framework, theories are conceptual constructs applying to models generated in the phenomenal world within limited contexts.The ontology of quantum theory principally rests on the view that entities in the world are pervasively correlated with one another not by means of probabilities as in the case of the classical theory, but by means of probability amplitudes involving finely tuned phases of quantum mechanical states (entanglement). The quantum correlations are shared globally in the process of environment-induced decoherence whereby locally generated correlations are removed, the removal being especially manifest in the case of systems that appear as classical ones, in which case the process is almost instantaneous, being, in all likelihood, driven by field fluctuations in the Planck regime. This points to factors of an unknown nature determining its finest details, since Planck scale physics remains an obscure terrain. In other words, the present day quantum theory holds within a limited context set by the Planck scale.
Quantum physics has dramatically reshaped our understanding of time and reality, revealing that the present moment occupies a uniquely privileged position within physical processes. In the first paper ("Quantum Physics Prefers the Present: A Temporal Ontology Grounded in Measurement"), we saw how quantum phenomena such as wavefunction collapse and measurement highlight the “now” as the only time when possibilities become actual. However, simply embracing presentism – the doctrine that only the present exists – is not enough. Presentism’s traditional metaphysical stance, which conflates existence with reality by declaring all non-present things unreal, runs into serious conceptual roadblocks when confronted with quantum experiments and the demands of causality and truth over time. This second paper advocates Existential Realism (ER) as a more nuanced and robust ontological framework that builds on those quantum insights while overcoming presentism’s limitations. By rigorously distinguishing existence from reality, ER provides a richer account of quantum phenomena – one that honors the special role of the present without erasing the past or negating the future. We will argue that ER better captures the ontology implied by quantum mechanics, from delayed-choice experiments and collapse theories to decoherence, and that it empowers a view of time where “becoming” and temporal agency are coherent and defensible. In short, Existential Realism preserves the empirical centrality of the present while acknowledging the tangible reality of past causes and future possibilities — making it a more comprehensive fit for quantum reality.
This article explores the potential for reconciling the fundamental paradoxes of quantum mechanics—the measurement problem, entanglement, and Schrödinger’s Cat—with advanced metaphysical frameworks from both classical Islamic philosophy and contemporary Western thought. It specifically examines the compatibility and explanatory power of Mulla Sadra’s transcendent philosophy, particularly his doctrines of Essential Movement, Existential Gradation, and the Primacy of Existence, alongside the modern philosophical interpretation of Presentist-Fragmentalism. By offering conceptual mappings and interpretations, this paper argues that these metaphysical perspectives can provide a more intuitive and coherent understanding of quantum phenomena, moving beyond the limitations of classical intuition and certain prevalent quantum interpretations.