Séminaire d'algèbre et de géométrie du 05-11-2025

Exposé de André Duarte

Le 05-11-2025 à 14:00, en P108 et en ligne.

Twisted group algebras of dihedral groups over finite fields

Résumé

Let F_q be a finite field and D_n the dihedral group of order 2n. I present explicit formulas for a complete set of 2-cocycles of D_n over F_q and compute the primitive central idempotents of F_q^αD_n. I also describe the Wedderburn decomposition of F_q^αD_n and determine the irreducible projective representations of D_n over F_q.