Random Walks, Arrangements, Cell Complexes, Greedoids, and Self-Organizing Libraries

Abstract

AbstractThe starting point is the known fact that some much-studied random walks on permutations, such as the Tsetlin library, arise from walks on real hyperplane arrangements. This paper explores similar walks on complex hyperplane arrangements. This is achieved by involving certain cell complexes naturally associated with the arrangement. In a particular case this leads to walks on libraries with several shelves.We also show that interval greedoids give rise to random walks belonging to the same general family. Members of this family of Markow chains, based on certain semigroups, have the property that all eigenvalues of the transition matrices are non-negative real and given by a simple combinatorial formula.Background material needed for understanding the walks is reviewed in rather great detail.KeywordsRandom WalkCell ComplexHomotopy TypeSign VectorHyperplane ArrangementThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.