How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
A complete positive family consists of effects
Statement
For a nonzero finite-dimensional complex-inner-product space , if is a finite complete positive family as defined in Finite positive effect family, then each is an effect: and are non-negative.
Facts & Assumptions
Given: A nonempty finite family of non-negative endomorphisms on with .
Finite positive effect family: a finite complete positive family has non-negative for every and its finite sum is ; an effect is a non-negative whose complement is non-negative.
Non-negative and positive operators: an operator is non-negative when it is self-adjoint and its quadratic form is nonnegative on every vector.
Proof
Fix . The family identity gives . For every , each is a nonnegative real by [F2]; their finite sum is therefore nonnegative, including the empty sum when . The sum is self-adjoint because each is self-adjoint and the sum is finite. Thus is non-negative.
Since is non-negative by [F1] and its complement is non-negative by step 1.1, it is an effect by the definition in [F1]. The index was arbitrary.
Depends on
Used by
Dependency tree · two levels
5 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- John Watrous, The Theory of Quantum Information, Chapters 1–3 (standard reference, not scraped)
- Ronald de Wolf, Quantum Computing: Lecture Notes, §15.1 (standard reference, not scraped)