gnostek1 / 5
- 01Brouwer proved in 1909 that any continuous map from a disk to itself must fix at least one point.
- 02The theorem applies in any dimension: a crumpled map of a country, laid on the country, touches one true point.
- 03Brouwer later rejected most of modern mathematics, becoming an 'intuitionist' who denied non-constructive proofs.