Mathematics Atlas

How Proof Is Made
Sign In
Text size
100%
Theme
Theorem

Borsuk-Ulam Theorem

Topology

Any continuous function from an n-dimensional sphere to n-dimensional Euclidean space must map some pair of antipodal points to the same point. Named for Karol Borsuk and Stanislaw Ulam, it has striking consequences, including that at any moment there exist two antipodal points on Earth with equal temperature and equal barometric pressure.

Facts
Statement
Every continuous function from an n-sphere into n-dimensional Euclidean space maps some pair of antipodal points to the same point. 1
Proof Year
1933 1
Lyusternik and Shnirelman had already stated the result in 1930; the first full proof, by Karol Borsuk, dates to 1933.
Classification
Statement Form
Existence Theorem 1
Connections

Has Statement Form

Entity-backed identity for the statement-form enum value this theorem already carries, resolved to a mathematics concept by an explicit value-to-entity map (phase 3 bucket conversion, docs\design_entity_backed_browse_buckets_20260928.md). The statement-form fact itself stays on the theorem unchanged.

In Branch

Sources
1. Borsuk-Ulam Theorem (Wikipedia)
Wikimedia FoundationHistory section
Quote, History section
The first proof was given by Karol Borsuk (1933), where the formulation of the problem was attributed to Stanisław Ulam.
View the Source
Comments (0)
No comments yet. Be the first to share a thought.
Reader Challenges (0)
No disputes yet. Spotted an error or a better source? Open the first one.