Videolibrary
RUS  ENG    JOURNALS   PEOPLE   ORGANISATIONS   CONFERENCES   SEMINARS   VIDEO LIBRARY   PACKAGE AMSBIB  
Video Library
Archive
Most viewed videos

Search
RSS
New in collection






Transformation groups 2017. Conference dedicated to Prof. Ernest B. Vinberg on the occasion of his 80th birthday
December 15, 2017 11:00–11:50, Moscow, Skolkovo Institute of Science and Technology, room 303
 


On some modules of covariants for a reflection group

C. De Concini

La Sapienza University, Romе, Italy

Number of views:
This page:98

Abstract: This is joint work with Paolo Papi. Let $W$ be an irreducible finite reflection group, $\mathfrak{h}$ its (complexified) reflection module. $\mathcal{H} = C[\mathfrak{h}]/I$, where $I$ is the ideal generated by polynomial invariants of positive degree. $A = (\Lambda (\mathfrak{h})\otimes \mathcal{H})^W$ is an exterior algebra and we completely determine the $A$-module structure of $N := hom_W (\mathfrak{h},\Lambda (\mathfrak{h})\otimes \mathcal{H})$.
When $\mathfrak{h}$ is the Cartan subalgebra of a simple Lie algebra $\mathfrak{g}$, it is well known and easy that $A$ is canonically isomorphic to $(\Lambda(\mathfrak{g}))^{\mathfrak{g}}$ and we verify that $N = hom_{\mathfrak{g}}(\mathfrak{g}, \Lambda(\mathfrak{g})$ as an $A$-module.
Finally if $V$ is an irreducible $g$-module whose zero weight space we denote by $V_0$, we construct a degree preserving map
$$hom_{\mathfrak{g}}(V,\Lambda(\mathfrak{g}))\to hom_W (V_0,\Lambda (\mathfrak{h})\otimes \mathcal{H})$$
which we conjecture to be injective. This conjecture implies a well known conjecture by Reeder.

Language: English
 
  Contact us:
 Terms of Use  Registration to the website  Logotypes © Steklov Mathematical Institute RAS, 2024