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arXiv · 1902.04339

Characteristic cycles and Gevrey series solutions of $A$-hypergeometric systems

Christine Berkesch·María-Cruz Fernández-Fernández
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Abstract

We compute the $L$-characteristic cycle of an $A$-hypergeometric system and higher Euler-Koszul homology modules of the toric ring. We also prove upper semicontinuity results about the multiplicities in these cycles and apply our results to analyze the behavior of Gevrey solution spaces of the system.

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Christine Berkesch, María-Cruz Fernández-Fernández. 2019-02-12. Characteristic cycles and Gevrey series solutions of $A$-hypergeometric systems. https://doi.org/10.2140/ant.2020.14.323

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