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arXiv · 2303.10458

Order and Gorenstein properties for lattice path matroid polytopes

Carolina Benedetti·Kolja Knauer·Jerónimo Valencia-Porras
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Abstract

We characterize matroids whose polytopes are order polytopes as a special class of lattice path matroids, called snakes. This shows that snakes are exactly the objects lying in the intersection of the Neggers-Stanley conjecture and a conjecture of de Loera, Haws, and K\"oppe. We then characterize Gorenstein lattice path matroid polytopes, yielding a new class of matroids satisfying the latter conjecture. Finally, we also show that lattice path matroids are exactly the class of positroids in which the coarsest subdivision of the matroid base polytope into translates of order polytopes is a (finest) matroidal subdivision.

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Carolina Benedetti, Kolja Knauer, Jerónimo Valencia-Porras. 2023-03-18. Order and Gorenstein properties for lattice path matroid polytopes. https://arxiv.org/abs/2303.10458

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