Density-functional representation limitation audit

Family 278: Failure of Kohn–Sham ensemble representation. First application triage, 9 October 2026 Australia/Brisbane.

Problem and potential new use

Electronic-structure researchers can flag universal claims that every interacting ground density has an ensemble representation by a local noninteracting potential.

Applicability and commercial boundary

The counterexample has a specific three-electron two-nucleus structure and nonnumerically specified charge. It does not make ordinary Kohn–Sham calculations invalid or provide a better density solver.

Initial business decision

Research infrastructure. Buyer budget, commercial novelty and profitability are unvalidated.

Next verification action

Inspect whether a concrete computable counterexample and observable diagnostic can be extracted.

Evidence scope

The catalog statement was individually reviewed. This record does not imply a manuscript proof review or formal-scope comparison. No independent Lean check was run. Source revision fd4aeeb2ee4fc729c18d98444fed42fd0529eeeb. See source metadata.

Main source

A Coulomb ground-state density without Kohn-Sham ensemble representation.