isEffectivelyClassical
plain-language theorem explainer
A quantum state encoded as an uncommitted ledger is effectively classical once one of its branches carries weight above the supplied threshold. Researchers deriving the measurement postulate from ledger commitment cite this predicate to mark the decoherence-driven transition to classical behavior. The definition is realized as a direct existential quantification over the branches list.
Claim. Let $L$ be an uncommitted ledger on $n$ components whose branches form a list of weighted outcomes normalized to sum to one, and let $t$ be a real threshold. Then $L$ is effectively classical relative to $t$ precisely when there exists a branch $b$ in the branches of $L$ such that the weight of $b$ exceeds $t$.
background
In the Recognition Science account of quantum measurement an uncommitted ledger is a structure whose branches field holds a list of potential outcomes, each carrying a weight that sums to one under the supplied normalization condition. This encodes a superposition state prior to ledger commitment. The module treats measurement as the forcing of commitment, with probabilities governed by recognition cost.
proof idea
The definition is a one-line abbreviation that directly asserts existence of a branch $b$ belonging to the branches list of the given uncommitted ledger whose weight is strictly larger than the threshold.
why it matters
This predicate supplies the domination criterion invoked by the downstream theorem decoherence_gives_classicality to conclude classical behavior. It operationalizes the module doc-comment that entanglement with many degrees of freedom renders uncommitted branches operationally inaccessible, thereby embedding the measurement postulate inside the ledger framework derived from the forcing chain.
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