Globally Irreducible Representations of Finite Groups and Integral Lattices

Pham Huu Tiep

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


The notion of globally irreducible representations of finite groups has been introduced by B. H. Gross, in order to explain new series of Euclidean lattices discovered recently by N. Elkies and T. Shioda using Mordell-Weil lattices of elliptic curves. In this paper we first give a necessary condition for global irreducibility. Then we classify all globally irreducible representations of L2(q) and 2B2(q), and of the majority of the 26 sporadic finite simple groups. We also exhibit one more globally irreducible representation, which is related to the Weil representation of degree (pn - 1)/2 of the symplectic group Sp2n (p) (p = 1 (mod 4) is a prime). As a consequence, we get a new series of even unimodular lattices of rank 2(pn - 1). A summary of currently known globally irreducible representations is given.

Original languageEnglish (US)
Pages (from-to)85-123
Number of pages39
JournalGeometriae Dedicata
Issue number1
StatePublished - 1997


  • Euclidean integral lattice
  • Even unimodular lattice
  • Finite simple group
  • Globally irreducible representation

ASJC Scopus subject areas

  • Geometry and Topology


Dive into the research topics of 'Globally Irreducible Representations of Finite Groups and Integral Lattices'. Together they form a unique fingerprint.

Cite this