This study proposes a counterfactual history and theoretical model of physics: assuming that Albert Einstein in the early 20th century had not prioritized the spacetime variability hypotheses of special and general relativity, but instead adopted the axiom that "an observer possesses no independent physical identity," thereby establishing "Relational Physicality." Within this framework, measurement outcomes are strictly defined as the state of interaction between the observer and the measured system, rather than intrinsic properties inherent to the measured system itself. This paper demonstrates that when the "observer" is demoted to an inseparable part of a physical system, the spatiotemporal relativity of special relativity and the measurement collapse problem of quantum mechanics can be consistently explained within a unified logical scheme. Physical facts are no longer objective realities independent of observational relations, but rather manifest representations of relational states among physical entities. This theoretical paradigm not only reconstructs the evolutionary path from classical to modern physics, but also provides a novel philosophical and physical foundation for unifying relativity and quantum mechanics.
This study proposes a counterfactual history and theoretical model of physics: assuming that Albert Einstein in the early 20th century had not prioritized the spacetime variability hypotheses of special and general relativity, but instead adopted the axiom that "an observer possesses no independent physical identity," thereby establishing "Relational Physicality." Within this framework, measurement outcomes are strictly defined as the state of interaction between the observer and the measured system, rather than intrinsic properties inherent to the measured system itself. This paper demonstrates that when the "observer" is demoted to an inseparable part of a physical system, the spatiotemporal relativity of special relativity and the measurement collapse problem of quantum mechanics can be consistently explained within a unified logical scheme. Physical facts are no longer objective realities independent of observational relations, but rather manifest representations of relational states among physical entities. This theoretical paradigm not only reconstructs the evolutionary path from classical to modern physics, but also provides a novel philosophical and physical foundation for unifying relativity and quantum mechanics.
Traditional physical ontology relies on the assumption of observer-independence, regarding a physical state as an intrinsic property that exists prior to measurement, with observation acting merely as a passive retrieval of pre-existing facts. This paper challenges this view and articulates a relational paradigm of physics: at fundamental levels, physical states are not absolute inherent attributes, but structural outputs generated through mutual interactions among the system, the environment, and the observational framework. By re-evaluating quantum collapse, quantum decoherence, and relational quantum mechanics, this study demonstrates how the choice of measurement basis and environmental interactions selectively determine pointer states and establish classicuality. Furthermore, the relational character of physical states is corroborated in macroscopic domains, including the dependency of thermodynamic entropy on coarse-graining and the reference-frame relativity of spatiotemporal states in general relativity and the Unruh effect. By reframing physics around interaction boundaries and information exchange, this paper establishes a relational realism that transcends both rigid objective realism and subjective idealism, offering insight into foundational problems in quantum gravity and quantum cosmology without appealing to external observers.
Quantum mechanics has transformed our understanding of reality, yet deep philosophical puzzles remain unresolved. Is there a consistent way to describe quantum measurement, the emergence of space and time, and the role of observers within one coherent ontology? This paper introduces Relational Quantum Dynamics (RQD), an interpretation that places relationships and information, not isolated objects, at the foundation of physics. Unlike traditional views, such as the Copenhagen interpretation, Everett's many-worlds theory, or hidden-variable approaches, RQD denies a single observer-independent reality, instead proposing that facts only become definite within specific observational contexts. It explicitly addresses foundational no-go results, including Bell's theorem, the Kochen-Specker theorem, and the Frauchiger-Renner paradox, by replacing absolute facts with relational, context-dependent truths. RQD rests on five interlocking principles: (1) quantum states are contextual and observer-relative, (2) time emerges from quantum interactions rather than existing as an external parameter, (3) space is constructed from patterns of quantum entanglement, (4) observers emerge as systems with highly integrated information, and (5) classical reality appears through quantum decoherence without special wavefunction collapse. Philosophically, RQD aligns with ontic structural realism, proposing that the fundamental ontology of the universe consists entirely of informational relations. It avoids collapsing into relativism or solipsism by ensuring intersubjective agreement through physical interactions. Ultimately, RQD may offer a unified picture in which quantum mechanics, spacetime, and observers are no longer separate domains but aspects of one interconnected informational web.
Quantum mechanics has transformed our understanding of reality, yet deep philosophical puzzles remain unresolved. Is there a consistent way to describe quantum measurement, the emergence of space and time, and the role of observers within one coherent ontology? This paper introduces Relational Quantum Dynamics (RQD), an interpretation that places relationships and information—not isolated objects—at the foundation of physics. Unlike traditional views, such as the Copenhagen interpretation, Everett’s many-worlds theory, or hidden-variable approaches, RQD denies a single observer-independent reality, instead proposing that facts only become definite within specific observational contexts. It explicitly addresses foundational no-go results, including Bell’s theorem, the Kochen–Specker theorem, and the Frauchiger–Renner paradox, by replacing absolute facts with relational, context-dependent truths. RQD rests on five interlocking principles: (1) quantum states are contextual and observer-relative, (2) time emerges from quantum interactions rather than existing as an external parameter, (3) space is constructed from patterns of quantum entanglement, (4) observers emerge as systems with highly integrated information, and (5) classical reality appears through quantum decoherence without special wavefunction collapse. Philosophically, RQD aligns with ontic structural realism, proposing that the fundamental ontology of the universe consists entirely of informational relations. It avoids collapsing into relativism or solipsism by ensuring intersubjective agreement through physical interactions. Ultimately, RQD may offer a unified picture in which quantum mechanics, spacetime, and observers are no longer separate domains but aspects of one interconnected informational web.
This paper explores a thought experiment: what would physics look like if quantum mechanics had not originated in the early 20th century from the exploration of the physical properties of microscopic particles (such as blackbody radiation and the particle and wave nature of electron orbits), but had instead been established first as a dynamics and probability theory about "physical measurement" itself? Through extrapolation from this historical turning point, this paper reconstructs a theoretical framework centered on "measurement dynamics," not on "particles," "wave functions," or "quantum fields" as fundamental ontology, but on a trinity of "system-measuring instrument-observer." Research shows that under this paradigm, the "measurement problem" is no longer a philosophical dilemma added after the theory's establishment, but rather the logical starting point for its construction; wave functions and quantum fields are relegated to derivative mathematical tools for calculating measurement probability distributions. This paper elaborates on the dynamics of measurement operators, the law of information evolution, and a systematic critique of counterfactual definiteness under this paradigm, providing a new and unified perspective for re-examining the fundamental interpretation of modern quantum mechanics.
In the late 1920s, Niels Bohr’s "Principle of Complementarity" became a cornerstone of the Copenhagen interpretation, asserting that the wave and particle aspects of micro-entities are mutually exclusive yet complementary properties manifested under distinct experimental arrangements. However, this classical-bound formulation inadvertently entangled quantum physics in a century-long ontological debate over what a microscopic system "really is." This paper presents a counterfactual historical and philosophical critique: had Bohr bypassed the binary framing of wave-particle duality and instead posited the Law of Coexisting Mutually Exclusive Descriptions—which dictates that a single physical system fundamentally possesses multiple, irreducible, and mutually exclusive descriptions simultaneously—the foundational paradigm of quantum mechanics would have undergone a decisive transformation. Under this proposed paradigm, the focus of quantum physics shifts from seeking a singular underlying "substance" to mapping how non-commutative, coexisting descriptions collectively construct physical reality. We demonstrate how this law redefines the quantum measurement problem, dissolves the misconception of "uncertainty" as an inherent ontological vagueness, and provides a unified conceptual framework for quantum entanglement and emergent spacetime in modern field theory. Ultimately, this work establishes a non-reductionist "Multitudinous Description Realism" that offers a clearer conceptual tool for contemporary quantum foundations and quantum information science.
Quantum mechanics reveals that physical quantities and informational states are not absolute but relational, depending on the context of interaction between systems. While classical physics already contained relational elements—most clearly in Galilean relativity and Einstein’s relational spacetime—the quantum domain extends relationality to physical properties and facts themselves. In this paper, I develop an info-computational perspective on relational quantum mechanics (RQM), conceiving observers as informational agents embedded within physical processes. Quantum states are understood as constraints on possible interactions rather than intrinsic attributes of isolated systems. I review key relational, perspectival, and information-theoretic approaches—including QBism, perspectival quantum realism, reference-frame–dependent observables, categorical quantum mechanics, and graph-based formalisms—and argue that they converge on a view of physics grounded in relations and information flow. Relational objectivity emerges through inter-agent translation rules rather than observer independence, providing a unified framework for understanding quantum measurement, inter-observer agreement, and physical ontology.