Two-Copy Distillability of Werner States
Is a Werner state that is not one-copy distillable ever two-copy distillable? The first open rung of the NPT bound-entanglement ladder, open since 2000.
- Result
- Disproved(see note)
- Status
- Resolved
- AI contribution
- AI-assisted
- Method
- Construction
- Field
- Entanglement theory
- Posed by
- —
- Year posed
- 2000
- Years open
- 26y
- Solved
- 2026-07-23
- Model
- GPT-5.5, GPT-5.6 Sol
- Vendor
- OpenAI
- Collaborators
- —
- Verification
- Unreviewed
- Publication
- Preprint
- Significance
- 35 / 100
- Disclosed cost
- —
- Wikipedia
- No dedicated article
What was actually shown
two-copy distillable iff already one-copy distillable
What the AI did
The proof by Fu, Gao and Park was AI-assisted and independently verified by the authors.
Verification
Author-verified arXiv preprint. Within days, two further groups posted independent proofs of the same theorem (arXiv:2607.24309, arXiv:2607.24479), which strengthens confidence but none is yet peer-reviewed.
Sources
arXiv:2607.21367 - A solution to 2-copy distillability of Werner states