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Peres and Horodeckis: partial-transpose and positive-map separability criteria

Contribution grade

Quantum information and entanglement theory · Exact theorem and reusable mathematical method

Reference score280,000Provisional editorial estimate of this exact contribution; its grade is assessed separately.

What changed

Every finite-dimensional bipartite separable state has positive partial transpose. The Horodecki positive-map characterization proves that this necessary test is also sufficient for 2x2 and 2x3 systems; in general separability is equivalent to positivity after applying every positive map to one subsystem.

Scientific scope

Every finite-dimensional bipartite separable state has positive partial transpose. The Horodecki positive-map characterization proves that this necessary test is also sufficient for 2x2 and 2x3 systems; in general separability is equivalent to positivity after applying every positive map to one subsystem. PPT is not sufficient in unrestricted higher dimensions. Testing only completely positive maps cannot characterize entanglement. Entanglement detection is not equivalent to a universal Bell-inequality violation test. The two original papers have distinct one-author and three-author bylines; low-dimensional positive-map decomposition uses earlier operator-algebra results.

Evidence

The linked original works support the scoped statement and contribution attribution. WRS has not independently replayed experiments or reconstructed a full mathematical proof. PPT is not sufficient in unrestricted higher dimensions. Testing only completely positive maps cannot characterize entanglement. Entanglement detection is not equivalent to a universal Bell-inequality violation test. The two original papers have distinct one-author and three-author bylines; low-dimensional positive-map decomposition uses earlier operator-algebra results.

Contributors

Provisional WRS assessment, edition 2026-10-23.9. Independent expert calibration is pending. This grade does not certify correctness or assign ownership.

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