Double flag varieties of Levi type with a finite number of orbits

Lucas Fresse; Kyo Nishiyama

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arXiv · 2609.21092

Double flag varieties of Levi type with a finite number of orbits

Lucas Fresse·Kyo Nishiyama

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Abstract

We consider a double flag variety of the form $L/Q\times G/P$ where $G$ is a connected reductive group and $L$ is a Levi subgroup of $G$. The Levi subgroup $L$ acts diagonally on this double flag variety and a basic problem is to classify pairs of parabolic subgroups $P\subset G$ and $Q\subset L$ such that there are finitely many orbits for the considered action. We solve this problem in the case where $G$ is the general linear group by using representations of quivers.

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BibTeX RIS

Lucas Fresse, Kyo Nishiyama. 2026-09-17. Double flag varieties of Levi type with a finite number of orbits. https://arxiv.org/abs/2609.21092

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