📜 Theorem, law or theory

Heine–Borel theorem

Teorema de Heine-Borel

Date
1895 · confidence medium
Place
Paris, France
Credited to
Émile Borel (building on earlier work by Eduard Heine)
Field
Knowledge & symbols

What was discovered

A theorem of real analysis stating that, in Euclidean space, a subset is compact if and only if it is closed and bounded; a fundamental tool of modern analysis.

Also called the Borel–Lebesgue lemma; Lebesgue contributed to its modern form.

What it led to

  • Modern formalization of the concept of compactness
  • Basis for later results in analysis and topology

Links

Sources✓ verified 2026-09-28