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Causal Computing Fields II: Measurement, Causal Coordinates, and the Limits of Quantum Projection

Son David Bolduc

Published Dec 22, 2025• 0 citations
Publisher

Abstract

This paper extends the theory of causal computing fields by addressing the measurement problem and the limits imposed by quantum projection. Building on the definition of computation as the autonomous relaxation of a physical field toward invariant attractors, the work examines whether causal-field computation alters the traditional incompatibility between position and momentum measurements in quantum mechanics. Rather than attempting to bypass quantum uncertainty through instrumental or environmental strategies, the paper systematically analyzes and rejects known approaches, including weak measurement, protective measurement, pre- and post-selection, and pure field readout. These dead ends are shown to fail because they retain the assumption that spatial position is a primitive observable. The central proposal is a distinction between spatial position and causal position. Spatial observables are treated as projections of a deeper causal state onto Euclidean coordinates, while causal position is defined as the alignment of a system within a causal state space structured by invariant axes. In this framework, quantum uncertainty arises from information loss under projection rather than from indeterminacy of the underlying causal state. The paper does not claim a violation of Heisenberg uncertainty. Instead, it reframes uncertainty as a property of spatial projection and identifies a narrow, falsifiable path by which causal computing fields could extend quantum mechanics without contradicting established results. Conditions for experimental discrimination between causal and quantum descriptions are explicitly stated.

DOI
10.5281/zenodo.18012876

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This paper extends the theory of causal computing fields by addressing the measurement problem and the limits imposed by quantum projection. Building on the definition of computation as the autonomous relaxation of a physical field toward invariant attractors, the work examines whether causal-field computation alters the traditional incompatibility between position and momentum measurements in quantum mechanics. Rather than attempting to bypass quantum uncertainty through instrumental or environmental strategies, the paper systematically analyzes and rejects known approaches, including weak measurement, protective measurement, pre- and post-selection, and pure field readout. These dead ends are shown to fail because they retain the assumption that spatial position is a primitive observable. The central proposal is a distinction between spatial position and causal position. Spatial observables are treated as projections of a deeper causal state onto Euclidean coordinates, while causal position is defined as the alignment of a system within a causal state space structured by invariant axes. In this framework, quantum uncertainty arises from information loss under projection rather than from indeterminacy of the underlying causal state. The paper does not claim a violation of Heisenberg uncertainty. Instead, it reframes uncertainty as a property of spatial projection and identifies a narrow, falsifiable path by which causal computing fields could extend quantum mechanics without contradicting established results. Conditions for experimental discrimination between causal and quantum descriptions are explicitly stated.
This paper completes the causal computing fields program by addressing the origin and ontological status of coordinates themselves. It argues that Euclidean spatial position is not a fundamental physical primitive and is therefore unsuitable for defining the true position of physical entities such as electrons. Building on the 90-degree orthogonality theorem, the paper shows that all stable and persistent rotational dynamics decompose into orthogonal causal roles rather than absolute spatial locations. By quotienting continuous angular degrees of freedom into invariant equivalence classes, it is demonstrated that all physically meaningful structure resides in orthogonality relations, not spatial coordinates. From this analysis, the Causal Cross is derived as the unique coordinate system that remains invariant under arbitrary spatial rotations, infinite spatial compression, and asymptotic time evolution. A complete causal state is defined without reference to Euclidean space and shown to be sufficient to classify physical systems prior to any projection into spatial observables. The paper systematically examines and rejects alternative constructions, including spatial relabeling, field-amplitude localization, detector-based mappings, and hidden Cartesian variables, demonstrating that each fails invariance or computability requirements. Spatial position is reinterpreted as an emergent, lossy projection of causal classification rather than an ontic attribute. Implications for quantum measurement are analyzed, with uncertainty arising from the non-invertibility of projection rather than intrinsic indeterminacy. Finally, explicit criteria are given for experimental falsification based on rotational invariance of causal classification under changing spatial detection geometries.
This paper completes the causal computing fields program by placing Causal Theory (CT) under explicit experimental constraint. Building on the projection operator and dimensional collapse formalism developed in earlier papers, it derives concrete, falsifiable predictions and defines strict criteria under which the theory must be validated or rejected. Rather than attempting to reproduce all quantum predictions by construction, the paper identifies regimes in which CT and standard quantum mechanics necessarily diverge. The central distinction is that quantum mechanics treats observable statistics as basis-dependent, whereas CT predicts invariance of causal rank and causal signature under rigid rotations of the measurement apparatus. Three classes of experiments are proposed. The first examines rotational invariance of causal signatures in interferometric geometries. The second tests for projection lag effects under rapid apparatus rotation, predicting threshold behavior absent in standard quantum theory. The third concerns post-convergence causal computing fields, where CT predicts observer-independent outcomes once the system has relaxed into a stable causal attractor. Secondary predictions concerning contextuality suppression, weak-measurement correlations, and robustness to detector geometry perturbations are also identified. Finally, the paper specifies non-negotiable criteria of refutation: any observed dependence of causal rank or causal signature on measurement basis or orientation falsifies the theory. With these conditions, Causal Theory exits the interpretational domain and enters experimental science. The remaining question is no longer conceptual but empirical: whether causal structure survives contact with experiment.
This paper completes the causal computing fields series by formalizing the projection operator that links causal-field dynamics to experimental observation. Projection is defined as a deterministic dimensional collapse that maps orthogonal causal gradients onto spatial detection statistics, rather than as a stochastic or observer-induced process. Starting from the Causal Cross, the paper introduces an explicit projection functional that transforms a causal signature into measurable spatial probabilities through the interaction between the causal tensor and detector geometry. In this framework, quantum uncertainty arises from projecting a fully orthogonal causal structure onto an incomplete spatial basis, not from indeterminacy of the underlying field. A toy model based on a quotiented circular degree of freedom is developed to demonstrate how causal equivalence classes generate familiar interference patterns under harmonic projection, without invoking intrinsic probabilistic postulates. The formalism is then applied to the electronic causal computing architecture introduced in earlier work, showing how measurement acts as a structural filter selecting invariant causal configurations after dissipation. The paper concludes by defining a concrete experimental falsification criterion: causal rank and causal signature must remain invariant under rotation of the measurement apparatus, even when spatial detection patterns change. By specifying this projection operator, the work provides the explicit mathematical and conceptual bridge required to connect Causal Theory to laboratory experiments and engineering implementations.
The quantum measurement problem arises from the apparent incompatibility between unitary evolution, definite outcomes, and the Born rule. Standard formulations treat measurement as a special physical process, introducing either collapse, branching, or hidden variables. In this paper we adopt a different approach. We do not modify quantum dynamics. Instead, we redefine the structure to which measurement applies. We introduce a minimal continuation-based framework in which physical systems are described by admissible succession structures and observable outcomes arise through coarse-graining projections. Measurement is defined as a non-injective projection from the space of admissible continuations to a finite outcome space. We show that non-injectivity generically induces apparent indeterminacy, while conditioning on the projection fiber replaces collapse. Within the weak-correlation regime, the Born rule emerges as the unique aggregation-stable weighting under additive continuation composition. Decoherence is modelled as constraint-induced suppression of continuation multiplicity, recovering the phenomenology of environmental decoherence without collapse. Under these conditions, three components of the measurement problem (definite outcomes, probabilistic weights, and classical stability) admit structural reformulations as consequences of projection and aggregation rather than postulates. A fourth component, the projection selection problem: which coarse-graining is realised in a given physical context: is identified as a residual open question of comparable difficulty to the preferred basis problem; the dissolution claim is conditional on its eventual resolution.
The measurement problem is commonly taken to indicate a fundamental conflict betweenthe linear, unitary dynamics of quantum mechanics and the definite outcomes observed inmeasurement processes. Standard responses typically resolve this tension by modifying thedynamics, enriching the ontology, or revising the interpretation of the quantum state.In this paper, we analyze the measurement problem from a projection-based perspectivein which quantum evolution and measurement outcomes are associated with ontologicallydistinct effective descriptions defined by incompatible invariance requirements. Within thisframework, quantum mechanics is characterized by unitary invariance and coherent superpo-sition, whereas measurement records are defined by definiteness, stability, and reproducibil-ity. The measurement problem arises when these distinct projection structures are implicitlyidentified or required to coexist within a single effective description.By analyzing measurement as a transition between such projections, we show that theappearance of wavefunction collapse does not require a physical dynamical process. Instead,collapse emerges as a necessary structural consequence of projecting a quantum descriptiononto a measurement domain that enforces different invariance constraints. This accountpreserves the formal structure and empirical success of quantum mechanics while motivatinga restrained ontological reading of its elements.More broadly, the analysis situates the measurement problem within a general patternin which foundational paradoxes arise at the boundaries between effective descriptions. Inthis sense, the resolution proposed here does not introduce new physics, but clarifies theontological scope and limits of quantum-mechanical description.
Recent works in foundations of quantum (field) theory and relativistic quantum information try to better grasp the interplay between the structure of quantum correlations and the constraints imposed by causality on physical operations. Chapter 1 is dedicated to the study of the conceptual implications of quantum nonlocality, a concept that subsumes that of entanglement in a certain way. We detail the recent information-theoretic approaches to understanding the structure of nonlocal correlations, and the issues the latter raise concerning the ability of local observers to isolate a system from its environment. Chapter 2 reviews in what sense imposing Poincare invariance affects entanglement detection and quantification procedures. This invariance ultimately forces a description of all quantum systems within the framework of quantum field theory, which leads to the impossibility of localized finite-energy states and to the divergence of all entanglement measures for local observers. We provide a solution to these two problems by showing that there exists a generic equivalence between a finite spatial resolution of the measurement apparatus and the exclusion of high-energy degrees of freedom from the definition of the observed system. This equivalence allows for an epistemic interpretation of the standard quantum formalism describing nonrelativistic localized systems and their correlations, hence a clarification of the origin of the finite measures of entanglement between such systems. Chapter 3 presents a recent theoretical framework that predicts the existence of correlations with indefinite causal order. In analogy to the information-theoretic approaches to nonlocal correlations, we introduce some principles that constrain the structure of such correlations, which is a first step toward a clear understanding of their physical origin.