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arXiv · 1405.5736

A generalised $τ$-invariant for the unequal parameter case

Meinolf Geck
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Abstract

In 1979, Vogan proposed a generalised $τ$-invariant for characterising primitive ideals in enveloping algebras. Via a known dictionary this translates to an invariant of left cells of finite Weyl groups. Although it is not a complete invariant, it is extremely useful in describing left cells. Here, we propose a general framework for defining such invariants which also applies to Hecke algebras with unequal parameters.

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Meinolf Geck. 2014-05-22. A generalised $τ$-invariant for the unequal parameter case. https://arxiv.org/abs/1405.5736

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