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arXiv · 0904.3371

Towards a Global Springer Theory II: the double affine action

Zhiwei Yun
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Abstract

We construct an action of the graded double affine Hecke algebra (DAHA) on the parabolic Hitchin complex, extending the affine Weyl group action constructed in \cite{GSI}. In particular, we get representations of the degenerate DAHA on the cohomology of parabolic Hitchin fibers. We also generalize our construction to {\em parahoric} versions of Hitchin stacks, including the construction of 'tHooft operators as a special case. We then study the interaction of the DAHA action and the cap product action given by the Picard stack acting on the parabolic Hitchin stack.

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Zhiwei Yun. 2009-04-22. Towards a Global Springer Theory II: the double affine action. https://arxiv.org/abs/0904.3371

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