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arXiv · 2003.13752

Parallel Computation of tropical varieties, their positive part, and tropical Grassmannians

Dominik Bendle·Janko Boehm·Yue Ren·Benjamin Schröter
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Abstract

In this article, we present a massively parallel framework for computing tropicalizations of algebraic varieties which can make use of finite symmetries. We compute the tropical Grassmannian TGr$_0(3,8)$, and show that it refines the $15$-dimensional skeleton of the Dressian Dr$(3,8)$ with the exception of $23$ special cones for which we construct explicit obstructions to the realizability of their tropical linear spaces. Moreover, we propose algorithms for identifying maximal-dimensional tropical cones which belong to the positive tropicalization. These algorithms exploit symmetries of the tropical variety even though the positive tropicalization need not be symmetric. We compute the maximal-dimensional cones of the positive Grassmannian TGr$^+(3,8)$ and compare them to the cluster complex of the classical Grassmannian Gr$(3,8)$.

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Dominik Bendle, Janko Boehm, Yue Ren, Benjamin Schröter. 2020-03-30. Parallel Computation of tropical varieties, their positive part, and tropical Grassmannians. https://arxiv.org/abs/2003.13752

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