Order-Chain Polytopes
نویسندگان
چکیده
Given two families X and Y of integral polytopes with nice combinatorial and algebraic properties, a natural way to generate new class of polytopes is to take the intersection P = P1 ∩ P2, where P1 ∈ X, P2 ∈ Y . Two basic questions then arise: 1) when P is integral and 2) whether P inherits the “old type” from P1,P2 or has a “new type”, that is, whether P is unimodularly equivalent to some polytope in X ∪ Y or not. In this paper, we focus on the families of order polytopes and chain polytopes and create a new class of polytopes following the above framework, which are named order-chain polytopes. In the study on their volumes, we discover a natural relation with Ehrenborg and Mahajan’s results on maximizing descent statistics.
منابع مشابه
Gorenstein Fano Polytopes Arising from Order Polytopes and Chain Polytopes
Richard Stanley introduced the order polytope O(P ) and the chain polytope C(P ) arising from a finite partially ordered set P , and showed that the Ehrhart polynomial of O(P ) is equal to that of C(P ). In addition, the unimodular equivalence problem of O(P ) and C(P ) was studied by the first author and Nan Li. In the present paper, three integral convex polytopes Γ(O(P ),−O(Q)), Γ(O(P ),−C(Q...
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