Causality in Quantum Theory: From Linearity to Relational Constraint

Causality has long been the backbone of physical explanation. In classical mechanics, one state leads to another through well-defined laws. In relativity, causes are bounded by light cones. But in quantum theory, the tidy picture of cause preceding effect begins to fray — especially in entangled systems and delayed-choice experiments.

The problem is not that quantum mechanics violates causality, but that it reveals a deeper structure beneath it — one where constraint and coherence take precedence over linear causal chains.

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1. The Classical Model: Locality and Temporal Order

• Causal models presume localised entities interacting through well-ordered time,

• A cause precedes an effect, and their relation can be traced through space and time,

• This works well for billiard balls, but breaks down in entangled systems, where outcomes correlate regardless of distance or order.

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2. The Relational Shift: From Event Chains to Field Coherence

• In a relational ontology, causality is not a line from A to B, but a pattern of constraint across a relational field,

• What happens “here” depends not on what happened “there” in a sequence, but on how possibilities cohere systemically,

• Instead of temporal sequences causing events, relational coherence permits transitions.

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3. Entanglement and the Illusion of Superluminal Influence

• When entangled particles exhibit correlated outcomes, no signal travels between them,

• The correlation arises from a shared structure of potential actualisation, not one outcome causing another,

• The “effect” is not distant from the “cause” — both are punctualisations of the same relational configuration.

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4. Causal Inference as Constraint Mapping

• In this view, what we call causal inference becomes the mapping of constraints within which transitions become possible or probable,

• Measurement doesn’t alter the past or send messages faster than light — it selects from a field of joint affordances,

• This makes quantum causality non-linear, non-local, and context-sensitive — not lawless, but structured differently.

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Closing

Quantum theory doesn’t abolish causality — it reweaves it.

Causality, in this light, is not about things bumping into each other, nor about chains of influence through space and time. It is about how a field of potential constrains what may become actual, and how relation configures resolution.

In our next post, we’ll explore how this reimagining of causality intersects with quantum field theory — where particles themselves dissolve into fields of relation.