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On exceptional rigid local systems

Michael Dettweiler·Stefan Reiter
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Abstract

We prove new instances of Simpson's rigidity conjecture which states that quasi-unipotent rigid local systems should be motivic. We construct new relative motives over the fourfold punctured Riemann sphere which give rise to $G_2$-rigid local systems which are not rigid in the group $\GL_7.$

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Michael Dettweiler, Stefan Reiter. 2006-09-05. On exceptional rigid local systems. https://arxiv.org/abs/math/0609142

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