David Hilbert

July 2026

Who he was

David Hilbert (1862–1943) was a German mathematician, one of the most influential of the 20th century, working at the University of Göttingen. Among a vast body of foundational work, he derived the field equations of general relativity through a variational (action-based) approach almost simultaneously with Einstein in November 1915 — a famous near-simultaneous discovery, worked out from a different mathematical starting point.

What he’s known for on this site

Hilbert appears twice on this site: as one of the two Göttingen mentors (with Felix Klein) who encouraged Emmy Noether’s work — and, according to a widely told account, responded to the faculty’s objection to hiring a woman by pointing out the university senate was “not a bathhouse” — and via Hilbert’s infinite hotel, his famous thought experiment illustrating that an infinite set can have the same cardinality as one of its own proper subsets, discussed in Embracing Infinity.

Catalog status: Proven Systems

Both the mathematics of infinite cardinality and the Einstein-Hilbert action underlying general relativity are rigorously proven, foundational results.

Mentioned on this site

• Emmy Noether — his role encouraging her theorem
• Embracing Infinity — the infinite hotel paradox

Where this touches PBT

Nothing here connects to PBT’s own claims specifically — Hilbert’s work is included as real mathematical/historical context behind results (Noether’s theorem, general relativity itself) that this site’s PBT content is built around or compared against.