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arXiv · 2609.07074

Fano Generalized Bott-Samelson Varieties

Narasimha Chary Bonala·Santosha Pattanayak·Yogendra Singh
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Abstract

The Bott-Samelson varieties provide natural desingularizations of Schubert varieties, and their generalizations, called generalized Bott-Samelson varieties, were constructed by Nicolas Perrin as towers of locally trivial fibrations with fibers isomorphic to Schubert varieties. In this article, we give a complete characterization of Fano and weak Fano generalized Bott-Samelson varieties. As a consequence, we recover the corresponding results for ($G$-)Bott-Samelson varieties and minuscule generalized Bott-Samelson varieties.

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Narasimha Chary Bonala, Santosha Pattanayak, Yogendra Singh. 2026-09-07. Fano Generalized Bott-Samelson Varieties. https://arxiv.org/abs/2609.07074

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