Summer School 2022 -  Cohomology, Geometry and Explicit number theory (COGENT)

Collection Summer School 2022 - Cohomology, Geometry and Explicit number theory (COGENT)

Organisateur(s) Institut Fourier, CNRS, UGA
Date(s) 13/06/2022 - 30/06/2022
URL associée https://if-summer2022.sciencesconf.org/
00:00:00 / 00:00:00
43 55

Basic concepts and notions of orthogonal representations are in-troduced. If X : G → GL(V ) is a K-representation of a nite group G it may happen that its image X(G) xes a non-degenerate quadratic form q on V . In this case X and its character χ : G → K, g 7 → trace(X(g)) are called orthogonal. If χ is an irreducible orthogonal character of even degree this form is unique up to scalars and there is a unique square class detχ in the character eld Q(χ) = Q(χ(g) | g ∈ G) such that given any eld L with a representation that aords χ, the determinant of the xed form q is det(q) = detχ(L×)2. In this talk we will discuss computational methods for determining this square class which is called the orthogonal determinant of χ. We will also briey mention theoretical tools for determining this square class.

Informations sur la vidéo

Dernières questions liées sur MathOverflow

Pour poser une question, votre compte Carmin.tv doit être connecté à mathoverflow

Poser une question sur MathOverflow




Inscrivez-vous

  • Mettez des vidéos en favori
  • Ajoutez des vidéos à regarder plus tard &
    conservez votre historique de consultation
  • Commentez avec la communauté
    scientifique
  • Recevez des notifications de mise à jour
    de vos sujets favoris
Donner son avis