Graph homotopy and Graham homotopy
نویسندگان
چکیده
Simple-homotopy for simplicial and CW complexes is a special kind of topological homotopy constructed by elementary collapses and expansions. In this paper we introduce graph homotopy for graphs and Graham homotopy for hypergraphs, and study the relation between these homotopies and the simplehomotopy for simplicial complexes. The graph homotopy is useful to describe topological properties of discretized geometric figures, while the Graham homotopy is essential to characterize acyclic hypergraphs and acyclic relational database schemes.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 241 شماره
صفحات -
تاریخ انتشار 2001