Nonsymmetric Koornwinder Polynomials and Duality
نویسنده
چکیده
In the fundamental work of Lusztig [L] on affine Hecke algebras, a special role is played by the root system of type C̃n. The affine Hecke algebra is a deformation of the group algebra of an affine Weyl group which usually depends on as many parameters as there are distinct root lengths, i.e. one or two for an irreducible root system. However in the C̃n case, the Hecke algebra H has three parameters, corresponding to the fact that there is a simple coroot which is divisible by 2.
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