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arXiv · 1811.08884

Computing Convex Hulls in the Affine Building of SL_d

Leon Zhang
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Abstract

We describe an algorithm for computing the convex hull of a finite collection of points in the affine building of SL_d(K), for K a field with discrete valuation. These convex hulls describe the relations among a finite collection of invertible matrices over K. As a consequence, we bound the dimension of the tropical projective space needed to realize the convex hull as a tropical polytope.

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Leon Zhang. 2018-11-21. Computing Convex Hulls in the Affine Building of SL_d. https://arxiv.org/abs/1811.08884

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