Cw Posets after the Poincare Conjecture
نویسنده
چکیده
Anders Björner characterized which finite graded partially ordered sets arise as the closure relation on cells of a finite regular CW complex. His characterization of these “CW posets” required each open interval (0̂, u) to have order complex homeomorphic to a sphere of dimension rk(u)− 2. Work of Danaraj and Klee showed that sufficient conditions were for the poset to be thin and shellable. The proof of the Poincare Conjecture enables the requirement of shellability to be replaced by the homotopy CohenMacaulay property. This expands the range of tools that may be used to prove a poset is a CW poset.
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تاریخ انتشار 2010