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Causal Sets as Event-Selection Shadows of Modal Triplet Theory

Peter Nero

Published Jan 15, 2026• 0 citations
Publisher

Abstract

Causal set theory describes spacetime as a discrete partially ordered set of events, while measurement theory treats events as irreversible outcomes of quantum dynamics. We show that both notions arise as the same effective four-dimensional shadow of coherence-selection events in Modal Triplet Theory (MTT). Selection events are defined as irreversible transitions between admissible coherent basins under noninvertible projection. We prove that these events generate a locally finite partial order, yielding an effective causal set whose event density, ordering, and approximate Lorentz invariance are fixed by coherent-sector bottleneck data rather than by ad hoc sprinkling assumptions. Deviations from Poisson statistics and exact Lorentz invariance are predicted near coherence-breakdown regions. We establish cross-sector closure: the same bottleneck data control event density, measurement and collapse thresholds, ultraviolet completion, and canonical geometric discreteness. All results are slab-local and admissibility-conditioned, identifying spacetime discreteness, causal order, and irreversibility as unified reduced-dynamical consequences of coherence breakdown.

DOI
10.5281/zenodo.18261722

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General relativity (GR) is naturally organized around spacetime events and their causal order, whereas quantum field theory (QFT) is formulated in terms of states, operators, and unitary evolution, without an intrinsic criterion for when a quantum process becomes a definite spacetime fact. We propose an event-centered framework in which events are locally irreversible records generated by quantum-environment interactions and serve as an interface between quantum dynamics and relativistic spacetime structure. Event anchoring is characterized operationally by three jointly sufficient conditions: local classicalization, redundant environmental recording, and irreversibility against recovery. Their joint satisfaction defines local generative freezing. We realize these criteria in an explicit repeated-collision open-system model. The model is illustrative rather than a derivation from relativistic QFT, but it remains globally unitary and yields the freezing time in closed form. For all admissible tolerances, local classicalization is certified no later than channel-level irrecoverability, and generically earlier. Full anchoring occurs only when both irrecoverability and the required record redundancy have been reached, producing irrecoverability-limited and redundancy-limited regimes. At the level of anchored records, physical history is therefore represented as a partially ordered causal skeleton of frozen events on which effective field-theoretic descriptions operate. The framework addresses event anchoring--when a candidate outcome becomes a stable spacetime fact--while remaining compatible with standard QFT and relativistic causality. It does not derive the Born rule or solve single-outcome selection, which belong to the separate problem of event generation.