Alphabeta Math
CounterexampleConstruction: Literature-sourcedVerification: AI-adaptedprecheck passjudge pass (gpt-5.6-terra)audited 2026-09-05
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 morphism of ringed spaces need not be a morphism of locally ringed spaces

Statement refuted

Every morphism of ringed spaces between locally ringed spaces is automatically a morphism of locally ringed spaces.

Facts & Assumptions

Given: A field k, the local ring A=k[y](y), and the field K=k(x).

[F1]

A morphism of ringed spaces between one-point spaces is exactly a ring map between their stalk rings (Morphisms of ringed spaces).

[F2]

A morphism of locally ringed spaces must induce local maps on stalks (Morphisms of locally ringed spaces).

[L1]

Counterexample

technique · direct
1.1

Regard ({},A) and ({},K) as one-point ringed spaces. The assignment yx defines a ring homomorphism AK, so by [F1] it defines a morphism of ringed spaces ({},K)({},A).

F1givenconstruct
2.1

The unique maximal ideal of A is (y) by [L1], while the unique maximal ideal of the field K is 0. Under the stalk map AK, the element y goes to the nonzero element x, hence to a unit of K. Therefore the image of (y) is not contained in 0, so the stalk map is not local. By [F2], the morphism is not a morphism of locally ringed spaces.

F2L1step 1.1
3.1

This gives a morphism of ringed spaces between locally ringed spaces that is not locally ringed. The statement is false.

step 1.1step 2.1

Depends on

Used by

Nothing in the library uses this result yet.

Dependency tree · two levels

11 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