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arXiv · 2111.13676

Generalized permutahedra and positive flag Dressians

Michael Joswig·Georg Loho·Dante Luber·Jorge Alberto Olarte
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Abstract

We study valuated matroids, their tropical incidence relations, flag matroids and total positivity. This leads to a characterization of permutahedral subdivisions, namely subdivisions of regular permutahedra into generalized permutahedra. Further, we get a characterization of those subdivisions arising from positive valuated flag matroids.

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Michael Joswig, Georg Loho, Dante Luber, Jorge Alberto Olarte. 2022-06-07. Generalized permutahedra and positive flag Dressians. https://doi.org/10.1093/imrn%2Frnac349

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