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arXiv · 2412.04870

$\PGL$ orbits on products of flag varieties

Izzet Coskun·Abuzer Gündüz
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Abstract

In this paper, we study the existence of a dense orbit for the diagonal $\PGL(n)$ action on self-products of partial flag varieties. We determine when there exists a dense orbit for flag varieties of the form $F(k_1, \dots, k_r; n)^m$ when $k_i = i$ or when $m=3$ and $k_i = \ell + i$ for some $\ell \geq 0$. We also show that certain infinite families of products do not have a dense orbit.

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Izzet Coskun, Abuzer Gündüz. 2024-12-06. $\PGL$ orbits on products of flag varieties. https://arxiv.org/abs/2412.04870

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