# Hilbert's twenty-third problem

> Promotes work on calculus of variations

**Wikidata**: [Q5761180](https://www.wikidata.org/wiki/Q5761180)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Hilbert's_twenty-third_problem)  
**Source**: https://4ort.xyz/entity/hilbert-s-twenty-third-problem