Alphabeta Math
ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedjudge pass (gpt-6-luna)verified 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.

Sensor placement along a high prior-variance direction

Example

Assume AC. Let θ∼N2(0,C) with C=diag⁡(9,1). Compare two zero-cost one-sensor designs with independent unit-variance Gaussian noise: d1 observes A1θ with A1=(1,0), and d2 observes A2θ with A2=(0,1). Their expected information gains are 12log⁡10 and 12log⁡2, respectively, so the sensor measuring the higher prior-variance direction is uniquely preferred.

Facts & Assumptions

Given: AC, the prior covariance C=diag⁡(9,1), the two row operators, and independent observation noise with covariance 1 for both designs.

[A1]

AC is inherited from the EIG/KL convention. The Axiom of Choice

[F1]

For C⪰0 and Γ≻0, EIG⁡=12log⁡det⁡(I+Γ−1/2ACATΓ−1/2). Linear Gaussian information gain has a log-determinant formula

[F2]

The natural logarithm is strictly increasing and log⁡1=0. Order, continuity, range, and the product, quotient, and reciprocal laws for the natural logarithm

Verification

Given: The hypotheses in the Example.

1.1A1F1givenalgebra

For d1, A1CA1T=9 and Γ1=1, so [F1] gives EIG⁡(d1)=12log⁡(1+9)=12log⁡10. For d2, A2CA2T=1 and Γ2=1, so [F1] gives EIG⁡(d2)=12log⁡(1+1)=12log⁡2.

2.1F2step 1.1algebra∎

The costs are equal and 10>2>0, so strict increase of the logarithm [F2] gives EIG⁡(d1)>EIG⁡(d2). Thus d1 is the unique maximizer among the two candidates.

Depends on

Used by

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Dependency tree · two levels

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