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arXiv · 2009.02125

On Schubert varieties of complexity one

Eunjeong Lee·Mikiya Masuda·Seonjeong Park
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Abstract

Let $B$ be a Borel subgroup of $\mathrm{GL}_n(\mathbb{C})$ and $\mathbb{T}$ a maximal torus contained in $B$. Then $\mathbb{T}$ acts on $\mathrm{GL}_{n}(\mathbb{C})/B$ and every Schubert variety is $\mathbb{T}$-invariant. We say that a Schubert variety is of complexity $k$ if a maximal $\mathbb{T}$-orbit in $X_w$ has codimension $k$. In this paper, we discuss topology, geometry, and combinatorics related to Schubert varieties of complexity one.

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BibTeXRIS

Eunjeong Lee, Mikiya Masuda, Seonjeong Park. 2020-09-04. On Schubert varieties of complexity one. https://doi.org/10.2140/pjm.2021.315.419

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