Alphabeta Math
CorollaryStatement: Literature-sourcedProof: AI-generatedverified 2026-09-26 (gpt-6-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.

A meromorphic essential singularity omits at most two sphere values

Statement

Assume the Axiom of Choice. Let f be meromorphic on a punctured disc 0<∣z−a∣<R with an essential singularity at a. Then at most two sphere values can be omitted on a punctured neighborhood of a; equivalently, with at most two sphere-value exceptions, every value occurs infinitely often in every punctured neighborhood of a.

Facts & Assumptions

Given: The Axiom of Choice and a meromorphic function with an essential singularity on 0<∣z−a∣<R.

[A1]

The Axiom of Choice is The Axiom of Choice; it supplies the premise of Great Picard in [L1].

[L1]

Under the Axiom of Choice, Great Picard holds for holomorphic functions and finite values (Great Picard theorem).

[L2]

Möbius transformations act biholomorphically on the sphere and can move any ordered triple of sphere points to any other (Every Möbius transformation is a biholomorphism of the Riemann sphere, A unique Möbius transformation carries any ordered triple of distinct sphere points to any other).

Proof

technique · direct
1.1L2givenassume-contrachoose

Suppose three distinct sphere values each failed to occur infinitely often in some punctured neighborhood of a. After passing to a common smaller neighborhood and then shrinking past their finitely many preimages, all three values are omitted. By [L2], choose a Möbius transformation M sending them to 0, 1, and ∞. Then g:=M∘f is holomorphic on that smaller punctured disc and still has an essential singularity at a, because a biholomorphic target change cannot turn an essential singularity into a removable singularity or pole.

2.1A1L1step 1.1discharge-contradiction

The function g omits the finite values 0 and 1, so [L1] under [A1] gives a contradiction. Thus at most two sphere values can fail the infinitely-often property, and every other sphere value occurs infinitely often in every punctured neighborhood.

3.1step 2.1∎

This is the meromorphic Great Picard conclusion.

Depends on

Used by

Nothing in the library uses this result yet.

Dependency tree · two levels

10 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