Energy-constrained diamond norms and their use in quantum information theoryResearch Paper
Motivation
We consider the family of energy-constrained diamond norms on the set of Hermitian-preserving linear maps (superoperators) between Banach spaces of trace class operators. We prove that any norm from this family generates the strong (pointwise) convergence on the set of all quantum channels (which is more adequate for describing variations of infinite-dimensional channels than the diamond norm topology). We obtain continuity bounds for information characteristics (in particular, classical capacities) of energy-constrained quantum channels (as functions of a channel) with respect to the energy-constrained diamond norms which imply uniform continuity of these characteristics with respect to the strong convergence topology.
This mission is the statement-level formalization of Energy-constrained diamond norms and their use in quantum information theory (arXiv:1706.00361v2). Every numbered result of the paper was scanned. The results stated here are open sorry goals, ready for solvers to prove.
What is formalized
7 statements of the paper are in Lean 4 (Mathlib 0df444a). The goal theorem is Proposition 3 A–B: general-input ECD convergence and strong topology (Abstract topology result, precisely Proposition 3 A–B, PDF p. 6). The milestones are the other numbered results, in the paper's order, each quoting the paper.
The paper's own objects are the definition item of this mission. Objects shared across papers come from the prove2quantum library and from earlier papers' missions, listed as references.
Provenance: prove2quantum's pipeline drafted each statement (gpt-6.1-sol on Stanford's Sherlock cluster). A blind read-back, written without seeing the paper, is attached to every item. An independent moderator compared each statement against the paper and passed the whole paper without edits.
Deferred results
13 results of the paper are not stated yet, because the library lacks an interface they need:
- §4, unnumbered: (2) is a norm on all L(A,B): A valid literal source claim on its printed domain; §4, unnumbered: (2) is a norm on all L(A,B) (source-ambiguity)
- Remark 1: extension to operator-norm-bounded HP subsets: A valid literal source claim on its printed domain; Remark 1: extension to operator-norm-bounded HP subsets (source-ambiguity)
- Proposition 4: output Holevo continuity and oscillator form: Adapters from accepted oscillator spectrum/entropy model to the closed-form coefficient-channel model, and actual sharpness constructions (hard)
- Remark 3: existence of an optimal t: A valid literal source claim on its printed domain; Remark 3: existence of an optimal t (source-ambiguity)
- Corollary 1: literal universal-metric claim: A valid literal source claim on its printed domain; Corollary 1: literal universal-metric claim (source-ambiguity)
- Remark 4: any metric generating strong topology: A valid literal source claim on its printed domain; Remark 4: any metric generating strong topology (source-ambiguity)
- Proposition 5: n-copy output QMI continuity: Adapters from accepted oscillator spectrum/entropy model to the closed-form coefficient-channel model, and actual sharpness constructions (hard)
- Remark 5: full QCMI extension of Proposition 5: Adapters from accepted oscillator spectrum/entropy model to the closed-form coefficient-channel model, and actual sharpness constructions; full extended QCMI (hard)
- Corollary 2: literal universal-metric claim: A valid literal source claim on its printed domain; Corollary 2: literal universal-metric claim (source-ambiguity)
- Proposition 6: Holevo and regularized classical continuity: Adapters from accepted oscillator spectrum/entropy model to the closed-form coefficient-channel model, and actual sharpness constructions (hard)
- Proposition 7 A–B: entanglement-assisted continuity: Adapters from accepted oscillator spectrum/entropy model to the closed-form coefficient-channel model, and actual sharpness constructions (hard)
- Corollary 3 A–B: literal universal-metric claim: A valid literal source claim on its printed domain; Corollary 3 A–B: literal universal-metric claim (source-ambiguity)
- §5.3: identity/vacuum sharpness examples: Adapters from accepted oscillator spectrum/entropy model to the closed-form coefficient-channel model, and actual sharpness constructions (hard)
Selected references
- Energy-constrained diamond norms and their use in quantum information theory, arXiv:1706.00361v2, https://arxiv.org/abs/1706.00361v2