Applications of Mathematics, Vol. 65, No. 6, pp. 703-726, 2020


Isocanted alcoved polytopes

María Jesús de la Puente, Pedro Luis Clavería

Received December 27, 2019.   Published online October 21, 2020.

Abstract:  Through tropical normal idempotent matrices, we introduce isocanted alcoved polytopes, computing their $f$-vectors and checking the validity of the following five conjectures: Bárány, unimodality, $3^d$, flag and cubical lower bound (CLBC). Isocanted alcoved polytopes are centrally symmetric, almost simple cubical polytopes. They are zonotopes. We show that, for each dimension, there is a unique combinatorial type. In dimension $d$, an isocanted alcoved polytope has $2^{d+1}-2$ vertices, its face lattice is the lattice of proper subsets of $[d+1]$ and its diameter is $d+1$. They are realizations of $d$-elementary cubical polytopes. The $f$-vector of a $d$-dimensional isocanted alcoved polytope attains its maximum at the integer $\lfloor d/3\rfloor$.
Keywords:  cubical polytope; isocanted; alcoved; centrally symmetric; almost simple; zonotope; $f$-vector; cubical $g$-vector; unimodal; flag; face lattice; log-concave sequence; tropical normal idempotent matrix; symmetric matrix
Classification MSC:  52B12, 15A80


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Affiliations:   María Jesús de la Puente (corresponding author), Universidad Complutense, Plaza de Ciencias 3, 28040 Madrid, Spain, e-mail: mpuente@ucm.es; Pedro Luis Clavería, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain, e-mail: plcv@unizar.es


 
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