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Cell-dimension simplification contract
Family 321: A counterexample to Wall's finite D(2) problem. First application triage, 9 October 2026 Australia/Brisbane.
Problem and potential new use
Record that specified homology vanishing of a finite three-dimensional complex does not guarantee a finite two-dimensional homotopy model.
Applicability and commercial boundary
Universal-cover and local-coefficient homology assumptions differ from ordinary sampled boundary matrices.
Initial business decision
Research reference or conditional symbolic/verification engineering. No recurring buyer need, practical implementation or profitability has been demonstrated. Defer a standalone commercial product until a constructive example and a measurable workflow improvement exist. These records also identify unsupported inferences that an evidence platform could flag.
Next verification action
Read the finite complex and exact obstruction before a topology simplification fixture.
Evidence scope
The repository catalog statement was individually read. Main-paper construction, effectiveness and selected formal-scope comparison remain queued for this record. No independent Lean verification was run. Source revision fd4aeeb2ee4fc729c18d98444fed42fd0529eeeb. See source metadata.