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arXiv · 1410.1495

Duality for Ext-groups and extensions of discrete series for graded Hecke algebras

Kei Yuen Chan
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Abstract

In this paper, we study extensions of graded affine Hecke algebra modules. In particular, based on an explicit projective resolution on graded affine Hecke algebra modules, we prove a duality result for Ext-groups. This duality result with an Ind-Res resolution gives an algebraic proof of the fact that all higher Ext-groups between discrete series vanish.

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Kei Yuen Chan. 2016-10-03. Duality for Ext-groups and extensions of discrete series for graded Hecke algebras. https://doi.org/10.1016/j.aim.2016.03.002

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