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arXiv · 1909.00327

Alcove paths and Gelfand-Tsetlin patterns

Hideya Watanabe·Keita Yamamura
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Abstract

In their study of the equivariant K-theory of the generalized flag varieties $G/P$, where $G$ is a complex semisimple Lie group, and $P$ is a parabolic subgroup of $G$, Lenart and Postnikov introduced a combinatorial tool, called the alcove paths model. It provides a model for the highest weight crystals with dominant integral highest weights, generalizing the model by semistandard Young tableaux. In this paper, we prove a simple and explicit formula describing the crystal isomorphism between the alcove paths model and the Gelfand-Tsetlin patterns model for type $A$.

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Hideya Watanabe, Keita Yamamura. 2021-07-01. Alcove paths and Gelfand-Tsetlin patterns. https://arxiv.org/abs/1909.00327

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