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arXiv · 1812.07335

Homomorphism Complexes and Maximal Chains in Graded Posets

Benjamin Braun·Wesley K. Hough
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Abstract

We apply the homomorphism complex construction to partially ordered sets, introducing a new topological construction based on the set of maximal chains in a graded poset. Our primary objects of study are distributive lattices, with special emphasis on finite products of chains. For the special case of a Boolean algebra, we observe that the corresponding homomorphism complex is isomorphic to the subcomplex of cubical cells in a permutahedron. Thus, this work can be interpreted as a generalization of the study of these complexes. We provide a detailed investigation when our poset is a product of chains, in which case we find an optimal discrete Morse matching and prove that the corresponding complex is torsion-free.

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Benjamin Braun, Wesley K. Hough. 2018-12-18. Homomorphism Complexes and Maximal Chains in Graded Posets. https://arxiv.org/abs/1812.07335

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