WebApr 11, 2024 · The relaxation complexity $${{\\,\\textrm{rc}\\,}}(X)$$ rc ( X ) of the set of integer points X contained in a polyhedron is the minimal number of inequalities needed to formulate a linear optimization problem over X without using auxiliary variables. Besides its relevance in integer programming, this concept has interpretations in aspects of social … WebTheorem 2.2. The convex polyhedron R[G, p] c Rn is (A, B)-invariant if and only if there exists a nonnegative matrix Y such that One advantage of the above characterization is that Theorem 2.2 applies to any convex closed polyhedron, contrarily to the characterization proposed in Refs. 12, 14, which applies only to compact polyhedra. The second ...
Introduction - Mathematical Sciences
WebUsing the Hurewicz theorem, you deduce at once that such a polyhedron [Edit: if it is simply connected] has trivial homotopy groups, so that it is weakly homotopy equivalent to a … WebJun 5, 2024 · In particular, it does not depend on the way in which the space is partitioned into cells. Consequently one can speak, for example, of the Euler characteristic of an … how to grow beard fuller
Efficient MIP techniques for computing the relaxation complexity
WebBy a (compact) polyhedron we mean a subspace of Rq, for some q, which can be triangulated by a finite, rectilinear, simplicial complex. It is to be understood that all the triangulations of polyhedra and subdivisions of complexes to which we refer are rectilinear. WebMar 26, 2024 · For compact polyhedra, collapsibility implies injectivity [a11] and injectivity implies topological collapsibility [a10]. There seems to be no known example (1996) of a topologically collapsible polyhedron which has no collapsible triangulation. References How to Cite This Entry: Collapsibility. Encyclopedia of Mathematics. WebAug 1, 1975 · For each integer n > 1 there is a compact, contractible 2-dimensional polyhedron X such that Xcannot expand to a collapsible polyhedron in fewer than n elementary PL expansions Proof. Let D be the polyhedron underlying a contractible 2-complex without free faces, (e.g. the dunce hat) and let X, be the wedge product of n … how to grow beard naturally at home