Many questions about the structure of Kac-Moody algebras, generalisations of Lie algebras to infinite dimensions remain unanswered. EU research helped relate their topological properties with analytical ones.
Kac-Moody algebras were independently introduced in the 1960s by Victor Kac and Robert Moody to generalise the finite-dimensional Lie algebras. In recent years, the theory has undergone such tremendous developments in various directions that it has become a standard tool in mathematics.
Further details: Algebras extend a traditionally finite-dimensional universe