Mathematician:Felix Hausdorff

German mathematician fundamental in the development of modern topology.

Also active in set theory, measure theory and function theory.

The first to formulate what is now known as the Generalized Continuum Hypothesis. Committed suicide in preference to being sent to an internment camp.

Nationality
German

History

 * Born: 8 Nov 1868 in Breslau, Germany (now Wroclaw, Poland)
 * Died: 26 Jan 1942 in Bonn, Germany

Theorems and Definitions

 * Hausdorff Maximal Principle
 * Baker-Campbell-Hausdorff formula
 * Gromov-Hausdorff Convergence
 * Hausdorff Paradox
 * Hausdorff Space (also known as a $T_2$ Space)
 * Hausdorff Measure
 * Hausdorff Dimension
 * Hausdorff Moment Problem

Books and Papers

 * 1891: Zur Theorie der astronomischen Strahlenbrechung (doctoral thesis)
 * 1908: Grundzüge einer Theorie der geordneten Mengen
 * 1914: Grundzüge der Mengenlehre
 * 1919: Dimension und äusseres Mass (in which Hausdorff Dimension was introduced)
 * 1921: Summationsmethoden und Momentfolgen

He also published works in the field of philosophy and literature under the pseudonym Paul Mongré:
 * 1897: Sant' Ilario: Thoughts from Zarathustra's Country
 * 1898: Das Chaos in kosmischer Auslese (a critique of metaphysics)
 * 1900: Ekstases (a book of poetry)
 * 1904: Der Arzt seiner Ehre