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LemmaStatement: AI-generatedProof: AI-generated
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.

Restriction of the base field for weight one

PDF p. 4: Property (2)

Statement

Let k be a field with prime subfield F, and let X be a quasi-compact quasi-separated k-scheme. Then X is a quasi-compact quasi-separated F-scheme, and the weight-one complex assigned to X in Motivic complexes and cohomology is the value at this same scheme of the Elmanto–Morrow prime-field functor. The small Nisnevich site of X and its sheaf of units depend on X, not on which of these two structure maps is retained.

Facts & Assumptions

Given: k, F, and X as in the statement.

Goal: Identify the scheme, motivic value, and small-site data used after restriction of scalars.

[F1]

The motivic complex over k is defined by restricting the Elmanto–Morrow functor on qcqs F-schemes (Motivic complexes and cohomology, Elmanto–Morrow motivic complex input).

Proof

1.1given

Composition of X→Spec⁡k with Spec⁡k→Spec⁡F changes neither the underlying scheme nor its quasi-compactness or quasi-separatedness. Thus X belongs to the prime-field domain.

2.1F1step 1.1∎

By [F1], evaluating the restricted functor on X is evaluation of the original functor on that same underlying F-scheme. The objects and morphisms of the small Nisnevich site are étale schemes over X and maps over X; its covers are specified by their underlying étale maps and residue-field lifting property. These data, and the units of the structure sheaves on them, are unchanged by forgetting the k-structure. Hence the asserted identifications hold.

Depends on

Used by · 1

Dependency tree · 3 levels

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