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ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedprecheck pass
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.

Worked example: splitting a four-velocity in an observer's rest frame

Example

Worked computation. In an inertial chart with η0=diag⁡(−1,1,1,1) let the observer be n=e0=(1,0,0,0) and let u=(5/4,3/4,0,0), a future unit timelike vector: η(u,u)=−25/16+9/16=−1. Then γ=−η(n,u)=5/4≥1, h(u)=u+η(n,u)n=u−(5/4)(1,0,0,0)=(0,3/4,0,0) lies in n⊥=span⁡(e1,e2,e3), and the relative velocity is w=c h(u)/γ=(0,3c/5,0,0). One checks u=γ(n+w/c)=(5/4)(1,3/5,0,0) and ∣w∣2=9c2/25=c2(1−γ−2)=c2(1−16/25). Also h(h(u))=h(u) and η(n,h(u))=0. This four-velocity is the one of the clock with coordinate velocity (3c/5,0,0) in Worked example: proper time and four-velocity of a straight worldline at beta = 3/5.

Facts & Assumptions

Given: An inertial chart with η0=diag⁡(−1,1,1,1), the observer n=e0=(1,0,0,0) and the vector u=(5/4,3/4,0,0).

[L1]

Decomposition (Norms of four-velocity and four-acceleration, and the observer rest-space decomposition): for future unit timelike n,u the projection is h(v)=v+η(n,v)n with image n⊥ and h∘h=h and η(n,h(v))=0; γ=−η(n,u)≥1, w=c h(u)/γ∈n⊥, u=γ(n+w/c), ∣w∣2=c2(1−γ−2)<c2, and γ=1  ⟺  u=n.

[L2]

Chart (Inertial frames and inertial charts of the affine Minkowski model, The Euclidean spatial structure and cross product of an inertial frame): the chart's observer is e0, and n⊥=span⁡(e1,e2,e3) is the Euclidean spatial space of the frame with ∣w∣=δ(w,w).

[L3]

Bilinearity (Lorentz forms of inertia (3,1,0) on a 4-dimensional real vector space): in the chart, η(v,z)=−v0z0+v1z1+v2z2+v3z3.

[L4]

Observer clause (Four-velocity and four-acceleration of a future timelike worldline): the four-velocity of the observer's own worldline with future unit timelike n is cn.

Verification

technique · direct
1.1givenL1L3

By [L3], η(u,u)=−25/16+9/16=−1 and η(n,n)=−1, so both n and u are unit timelike; both are future because their first coordinates are positive and u0=5/4>∣usp∣=3/4, n0=1>0; hence [L1] applies.

2.1step 1.1L1L3

Direct computation in the chart: γ=−η(n,u)=5/4, and h(u)=u+η(n,u)n=u−(5/4)(1,0,0,0)=(0,3/4,0,0).

3.1step 2.1L1L2L3

The vector h(u)=(0,3/4,0,0) lies in span⁡(e1,e2,e3)=n⊥ by [L2], and η(n,h(u))=−1⋅0+0=0 by [L3]; idempotence h(h(u))=h(u) holds because h(u)∈n⊥ is fixed by h by [L1].

4.1step 2.1step 3.1L1L2

The relative velocity is w=c h(u)/γ=(0,3c/5,0,0) with ∣w∣2=9c2/25 by [L2]; the split identity gives u=γ(n+w/c)=(5/4)(1,3/5,0,0)=(5/4,3/4,0,0) and the Lorentz-factor identity ∣w∣2=c2(1−γ−2)=c2(1−16/25)=9c2/25, both by [L1].

5.1step 4.1L1L4∎

By [L4] the observer's four-velocity is c n=(c,0,0,0); since γ=5/4≠1, the criterion of [L1] gives u≠n, so the clock's four-velocity cu differs from the observer's and the split is nondegenerate.

Remarks

  • The split is algebraic, not dynamic. The computation uses only the projection h, the inner product and the definitions of γ and w; no differentiation, no dynamics and no physical measurement is involved.

  • Companion clock. The dimensionless four-velocity u=(5/4,3/4,0,0) is the one of the straight clock with coordinate velocity (3c/5,0,0) worked out in Worked example: proper time and four-velocity of a straight worldline at beta = 3/5; the split above re-derives that clock's relative velocity without using its worldline.

Depends on

Dependency tree · 2 levels