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Temporal Bell Inequalities and Global Consistency in Modal Triplet Theory

Peter Nero

Published Jan 10, 2026• 0 citations
Publisher

Abstract

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.

DOI
10.5281/zenodo.18208884

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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.
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.
Leggett-Garg inequalities are tests of macroscopic realism that can be violated by quantum mechanics. In this letter, we realise photonic Leggett-Garg tests on a three-level system and implement measurements that admit three distinct measurement outcomes, rather than the usual two. In this way we obtain violations of three- and four-time Leggett-Garg inequalities that are significantly in excess of those obtainable in standard Leggett-Garg tests. We also report violations the quantum-witness equality up to the maximum permitted for a three-outcome measurement. Our results highlight differences between spatial and temporal correlations in quantum mechanics.
Leggett-Garg inequalities are tests of macroscopic realism that can be violated by quantum mechanics. In this letter, we realise photonic Leggett-Garg tests on a three-level system and implement measurements that admit three distinct measurement outcomes, rather than the usual two. In this way we obtain violations of three- and four-time Leggett-Garg inequalities that are significantly in excess of those obtainable in standard Leggett-Garg tests. We also report violations the quantum-witness equality up to the maximum permitted for a three-outcome measurement. Our results highlight differences between spatial and temporal correlations in quantum mechanics.
Violations of Bell inequalities are commonly interpreted as evidence for nonlocal influences or as constraints on realist descriptions. We show that the failure of Bell-type factorizability arises naturally when observable outcomes are obtained through a non-injective mapping from an underlying configuration space. In this setting, the standard factorization assumption can be viewed as an implicit requirement that observable variables admit a jointly factorizable completion at the underlying level. We demonstrate that this requirement need not hold when the mapping from underlying configurations to observables is many-to-one. The resulting breakdown of probabilistic factorization does not rely on superluminal dynamics or hidden causal influences, but follows from information loss under projection. Observable outcomes correspond to equivalence classes of underlying configurations, preventing the assignment of independent local variables. We illustrate this mechanism with an explicit toy model producing Bell–CHSH violations while preserving operational no-signalling and statistical independence of measurement settings. The model is not intended to reproduce quantum correlations quantitatively, and may exceed the Tsirelson bound; its role is to isolate the structural origin of the violation. This analysis does not contradict Bell’s theorem, but identifies a class of effective descriptions for which its factorizability assumption does not apply. The framework preserves locality at the underlying level, introduces no additional hidden-variable dynamics, and does not modify quantum mechanics. It clarifies how classical factorization is recovered in regimes where the effective mapping becomes approximately injective. In the operator language of quantum theory, the same mechanism admits a natural reformulation in terms of reduction to an effective observable subalgebra by a noncommutative conditional expectation.
Violations of Bell inequalities are commonly interpreted as evidence for either nonlocal dynamics or the failure of classical realism. In this work, we show that Bell-type correlations can arise without invoking superluminal influences, retrocausality, or local hidden variables, provided that the mapping between underlying configurations and observable outcomes is non-injective. We study a class of effective models in which multiple underlying states correspond to the same observable description. Such non-injective projections generically induce non-factorizable joint probability structures at the level of observables, even when the underlying description itself is fully local and deterministic. As a result, the statistical assumptions required to derive Bell inequalities are violated at the effective level, while locality is preserved at the underlying level. Within this framework, quantum correlations emerge as structural features of projected descriptions rather than as signatures of nonlocal causation. We clarify the precise assumption of Bell’s theorem that fails in this setting and show how classical behavior is recovered in regimes where the effective projection becomes approximately injective, suppressing nonlocal correlations through decoherence and environmental coarse-graining. Our results suggest that Bell inequality violations need not reflect a fundamental nonlocality of nature, but may instead indicate intrinsic information loss induced by non-injective mappings between underlying configurations and observable descriptions.
This paper asks a deliberately narrower question than its predecessor: when does a Modal Triplet Theory (MTT) description reconstruct the standard nonrelativistic de Broglie-Bohm dynamics? We first specify the complete lower pilot-wave record. In addition to a complex Hilbert space and self-adjoint Schrodinger Hamiltonian, that record contains a physical configuration manifold, an actual configuration, a selected probability current, a guidance field and maximal flow, an equilibrium measure, subsystem and instrument data, a locality contract, and source and error certificates. For a regular spinless scalar Schrodinger model the standard current obeys a continuity equation, and velocity equals current divided by density away from nodes. Equivariance then propagates an initially chosen wavefunction-squared distribution. These facts are standard lower-level mathematics: continuity alone neither selects the actual configuration nor derives the initial equilibrium distribution, and it does not uniquely select the current because divergence-free modifications preserve the same continuity equation. The MTT result is therefore conditional. If one selected upper state emits the full pilot-wave record and its state, dynamics, configuration decoder, current, instruments, and records form commuting descent diagrams, then MTT reconstructs Bohmian trajectories and their operational statistics on the declared interval. The current canonical geometry is a ten-dimensional bundle over a four-dimensional Lorentzian base with a compact six-dimensional fibre; the former literal product of four-dimensional spacetime and three independent internal factors is not used. Failure of the reconstruction means that a required current, decoder, flow, or stable continuation is unavailable. It does not follow from the absence of a right inverse, and it does not establish that Bohmian mechanics is globally impossible. Standard global-existence results cover broad Hamiltonian classes for almost every equilibrium initial configuration. Entangled guidance is explicitly nonlocal in physical configuration space. Operational no-signalling can nevertheless hold in quantum equilibrium, while an MTT claim of upper-world locality requires a separate descent theorem preserving settings, local algebras, records, and independence assumptions. Measurement is treated as an ordinary system-apparatus interaction with an effective conditional wavefunction, not automatically as an admissibility-barrier crossing. The selected q=79 binary recorder provides an exact stopped operational output measure on its declared commuting Fock domain, but it does not yet source arbitrary Bohmian equilibrium ensembles or one uniquely actual history. The paper thus establishes a precise regime-limited reconstruction and a finite completion contract, not a universal derivation or a no-hidden-variable theorem.