Alphabeta Math

The Topology of Euclidean Space — Examples

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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.

✓ 3 results · all verified · 3 also independently AI-judged
Every result on this page is machine-checked by a proof checker and read in full and owner-audited; the judge is an additional, independent cross-model AI review of the proofs; all 3 also cleared it.
1 · Prerequisites
2 · Logical flowchart

3 · Items

Example

The Euclidean closed ball and sphere worked through the compactness equivalence chart

Counterexample

The open unit ball in ℝⁿ is bounded and not compact

Counterexample

ℝⁿ is closed and unbounded and is not compact for n≥1

Example

The straight segment between two points of an open Euclidean ball stays in the ball

Example

GL₁(ℝ)=ℝ∖{0} is disconnected, whereas ℝ²∖{0} is polygonally connected

Counterexample

An infinite particular-point space is pseudocompact and not compact

Sources