Let g \mathfrak {g} be a complex semisimple Lie algebra. We give a classification of contravariant forms on the nondegenerate Whittaker g \mathfrak {g} -modules Y ( χ , η ) Y(\chi , \eta ) introduced by Kostant. We prove that the set of all contravariant forms on Y ( χ , η ) Y(\chi , \eta ) forms a vector space whose dimension is given by the cardinality of the Weyl group of g \mathfrak {g} . We also describe a procedure for parabolically inducing contravariant forms. As a corollary, we deduce the existence of the Shapovalov form on a Verma module, and provide a formula for the dimension of the space of contravariant forms on the degenerate Whittaker modules M ( χ , η ) M(\chi , \eta ) introduced by McDowell.
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Globally irreducible Weyl modules for quantum groups
The authors proved that a Weyl module for a simple algebraic group is irreducible over every field if and only if the module is isomorphic to the adjoint representation for $$E_{8}$$ or its highest weight is minuscule. In this paper, we prove an analogous criteria for irreducibility of Weyl modules over the quantum group $$U_{\zeta}({{\mathfrak g}})$$ where $${\mathfrak g}$$ is a complex simple Lie algebra and $$\zeta$$ ranges over roots of unity.
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- Award ID(s):
- 1701768
- PAR ID:
- 10106709
- Date Published:
- Journal Name:
- Springer Proceedings in Mathematics and Statistics (Geometric and Topological Aspects of the Representation Theory of Finite Groups), Springer-Verlag
- Volume:
- 242
- Page Range / eLocation ID:
- 313-336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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