2009/03/19 by Maakestad, Helge Øystein
#14L30 #14N15 #17B10 #Algebraic Geometry (math.AG) #FOS: Mathematics #Representation Theory (math.RT)
paper · doi:10.48550/arxiv.0903.3291
Let G be a semi simple linear algebraic group over a field of characteristic zero and let V be a finite dimensional irreducible G-module with highest weight vector v. Let P in G be the parabolic subgroup fixing v and let g=Lie(G). We get a canonical filtration of V by P-modules Uk(g)v where Uk(g) is the filtration of the universal enveloping algebra U(g). This filtration was in a previous paper studied in the case where P in G=SL(E) is the subgroup fixing an m-dimensional subspace. The aim of this paper is to use higher direct images of G-linearized sheaves, filtrations of generalized Verma modules and annihilator ideals of highest weight vectors to give a basis for Uk(g) and to compute its dimension in the case where P in SL(E) is the parabolic group fixing a flag in E. We also interpret the filtration Uk(g) in terms of SL(E)-linearized jet bundles on SL(E)/P.