Alphabeta Math
ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedverified 2026-10-22 (gpt-6.1-sol)
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.

An unobserved state mode

Example

Take d=2, one input, one output, A=[1002], B=02×1, and C=[10]. For every finite horizon q≥1 with zero inputs, the distinct initial states x0=(0,0)T and x0′=(0,1)T produce the same exact output sequence, namely yk=0 for all 0≤k<q. The finite observability matrix has rank 1<2.

Facts & Assumptions

Given: The displayed matrices, zero inputs, a finite horizon q≥1, and the two stated initial states.

[F1]

Discrete linear input-state-output experiments: the state evolves by xk+1=Axk+Buk and each exact output is yk=Cxk.

[F2]

Finite observability identifies the initial state: for known A,C and inputs, the initial-state output map is injective exactly when Oq=[C;CA;…;CAq−1] has rank d.

Verification

1.1givenF1algebra

The first initial state remains zero because B=0, so its outputs are all zero. For the difference e2=(0,1)T, Ae2=2e2; induction gives Ake2=2ke2 for each k≥0. Since Ce2=0, every output difference is CAke2=0. Thus the two distinct initial states produce identical outputs at all samples.

2.1givenF2step 1.1algebra

For each j≥0, CAj=[1,0], so Oq consists of q copies of [1,0] and has rank 1. Since 1<d=2, [F2] implies that the initial-state output map is noninjective for every q≥1.

3.1step 1.1step 2.1∎

The initial states in step 1.1 are different but have the same complete observed sequence, so no data-only rule can recover both states exactly in this experiment.

Depends on

Used by

Nothing in the library uses this result yet.

Dependency tree · two levels

16 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