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Entanglement, Locality, and Measurement from Coherent Sector Dynamics

Peter Nero

Published Jan 15, 2026• 0 citations
Publisher

Abstract

Algebraic quantum field theory (AQFT) enforces relativistic locality at the level of observable algebras while allowing globally entangled states, but it does not explain why physically realized states are typically entangled, how entanglement propagates, or how measurement reduces entanglement without enabling superluminal signaling. We present an AQFT-compatible framework in which physically admissible states are restricted to those induced by coherent-sector dynamics in Modal Triplet Theory (MTT), characterized by bounded geometry, a uniform spectral gap, bounded coherent projectors, and disturbance–damping stability. Within this restricted state class, entanglement is interpreted as a global coherence constraint in configuration space, while microcausality, isotony, and the time-slice property remain exact on spacetime. Measurement is modeled as localized disturbance followed by stabilization into admissible basins, yielding partial disentanglement. Standard Bell/CHSH and temporal Bell (Leggett–Garg) violations are recovered without nonlocal influence, and entanglement spreading via mediated interactions is explained as causal propagation through common ancestors subject to finite-speed bounds. The framework unifies AQFT locality with the MTT analyses of measurement and Bell phenomena without modifying quantum field theory axioms.

DOI
10.5281/zenodo.18261392

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Algebraic quantum field theory (AQFT) enforces relativistic locality at the level of observable algebras while allowing globally entangled states, but it does not explain why physically realized states are typically entangled, how entanglement propagates, or how measurement reduces entanglement without enabling superluminal signaling. We present an AQFT-compatible framework in which physically admissible states are restricted to those induced by coherent-sector dynamics in Modal Triplet Theory (MTT), characterized by bounded geometry, a uniform spectral gap, bounded coherent projectors, and disturbance–damping stability. Within this restricted state class, entanglement is interpreted as a global coherence constraint in configuration space, while microcausality, isotony, and the time-slice property remain exact on spacetime. Measurement is modeled as localized disturbance followed by stabilization into admissible basins, yielding partial disentanglement. Standard Bell/CHSH and temporal Bell (Leggett–Garg) violations are recovered without nonlocal influence, and entanglement spreading via mediated interactions is explained as causal propagation through common ancestors subject to finite-speed bounds. The framework unifies AQFT locality with the MTT analyses of measurement and Bell phenomena without modifying quantum field theory axioms.
Temporal Bell inequalities, such as the Leggett–Garg inequalities, test whether a singlesystem can be described by a time-local realist model. Quantum mechanics violates theseinequalities while preserving operational causality. In this work we give a proof-forwardaccount of temporal Bell inequalities within Modal Triplet Theory (MTT). We show that any temporally factorized realist model satisfies the Leggett–Garg bound.We then demonstrate that MTT generically violates temporal factorization because physicallyadmissible histories are selected by global coherence and fixed-point constraints, ratherthan by independent time-local hidden variables. Despite this failure of temporalfactorization, MTT preserves no-retro-signaling: later measurement choices do not alterearlier observable marginals. As a result, MTT reproduces standard quantum Leggett–Garg violations without invokingretrocausal dynamics or abandoning realism of the underlying modal configuration.Temporal Bell violations and spatial Bell nonlocality are identified as two projections ofthe same global-consistency mechanism. The framework is fully compatible with currentexperiments and standard quantum predictions.
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This paper surveys the issue of relativistic causality within the framework of algebraic quantum field theory (AQFT). In doing so, we distinguish various notions of causality formulated in the literature and study their relationships, and thereby we offer what we hope to be a useful taxonomy. We propose that the most direct expression of relativistic causality in AQFT is captured not (as has sometimes been claimed) by the spectrum condition but rather by the axiom of local primitive causality, in that it entails a form of local determinism for quantum fields which generalizes the constraint of no superluminal propagation of classical field theories to relativistic quantum field theory. We discuss the status of the axiom of micro-causality by locating its place within a large family of separability/independence/locality conditions developed for AQFT and also by relating it to so-called no-signalling theorems. And we also provide a critical survey of attempts to understand the implications for relativistic causality of the distant correlations endemic to the states in models of AQFT satisfying the standard axioms, and we provide an assessment of attempts to employ Reichenbach's common cause principle in AQFT to defuse worries that these distant correlations implicate direct causal connections between relatively spacelike events.
This paper presents a finite, regulator-based resolution of quantum entanglement, extending the Dual Regulator Framework to nonlocal correlations while preserving causality, locality of dynamics, and relativistic consistency. Entanglement is shown to arise entirely within the virtual domain, which lacks spatial topology and is regulated by the finite invariant Λφ=ln⁡(φ2),\Lambda_\varphi = \ln(\varphi^2),Λφ=ln(φ2), while decoherence and measurement occur exclusively in the real domain, regulated by the Resolution Gap (RG). Because entangled correlations never propagate through real spacetime, their strength is shown to be exactly independent of spatial separation, without invoking superluminal influence or observer-dependent collapse. Bell inequality violations are derived from domain structure alone. The framework predicts a finite correction to the standard Tsirelson bound arising from virtual-domain regulation, yielding a testable enhancement at high precision. No hidden variables, signaling mechanisms, or modifications to relativistic causality are introduced. Decoherence of entangled systems is shown to be additive across subsystems and governed by regulator ratios rather than ad hoc environmental postulates. The Born rule emerges from symmetric coupling across the virtual–real interface, consistent with prior papers in the series. A companion computational validation script numerically reproduces all constants and predicted correlation bounds using standard numerical libraries. All results are reproducible and contain zero adjustable parameters. This work constitutes Paper III in a planned sequence addressing foundational inconsistencies in quantum field theory, following finite resolutions of measurement and wave–particle duality. Licenses Creative Commons Attribution Non Commercial No Derivatives 4.0 International
The Einstein-Podolsky-Rosen (EPR) paradox challenges the completeness of quantum mechanics under the assumptions of separability and locality, while Bell's theorem and its loophole-free experimental confirmations rule out local hidden variables and establish that entangled correlations are nonlocal yet no-signaling. This paper formulates, within the spacetime-quantum unified-field theory, a self-contained resolution of the paradox. Starting from the six axioms of the theory, we model the entangled pair as two local excitations of the single global spacetime-quantum field, a coherent superposition of discrete spacetime quanta (Axiom 1). We show that the EPR elements of reality are not attributes of the separated subsystems but properties of the global coherent configuration established within the common past light cone, so that EPR's tacit separability premise fails in this ontology (Axioms 1 and 5). Measurement is identified as a strictly local energy exchange (Axioms 2 and 5) whose influence propagates at most at the speed of light by the local hyperbolic master equation (Axiom 3), and we prove, by the invariance of the reduced density matrix, that no signaling is possible. The Bell correlations are reproduced as a consistency condition inherited from the standard-model sector (Axiom 4), with the Tsirelson bound 2√2 following from the no-signaling structure. Complete derivations of the correlation function, the Clauser-Horne-Shimony-Holt inequality and its violation, the no-signaling theorem, the local measurement model, and the coherence-entanglement relation are provided in the appendices.