THE q-SCHUR ALGEBRAS AND q-SCHUR DUALITIES OF FINITE TYPE

作者:Luo, Li*; Wang, Weiqiang
来源:Journal of the Institute of Mathematics of Jussieu, 2022, 21(1): 129-160.
DOI:10.1017/S1474748020000031

摘要

We formulate a q-Schur algebra associated with an arbitrary W-invariant finite set X-f of integral weights for a complex simple Lie algebra with Weyl group W. We establish a q-Schur duality between the q-Schur algebra and Hecke algebra associated with W. We then realize geometrically the q-Schur algebra and duality and construct a canonical basis for the q-Schur algebra with positivity. With suitable choices of X-f in classical types, we recover the q-Schur algebras in the literature. Our q-Schur algebras are closely related to the category O, where the type G(2) is studied in detail.