Complexity of simplicial homology and independence complexes of chordal graphs

نویسندگان

  • Michal Adamaszek
  • Juraj Stacho
چکیده

We prove the NP-hardness of computing homology groups of simplicial complexes when the size of the input complex is measured by the number of maximal faces or the number of minimal non-faces. The latter case implies NP-hardness of the homology problem for clique and independence complexes of graphs. Our approach is based on the observation that the homology of an independence complex of a chordal graph can be described using what we call strong induced matchings in the graph (also known as cross–cycles). We show that finding such a matching of a specified size in a chordal graph is NP-hard. We further study the computational complexity of finding any cross–cycle in arbitrary and chordal graphs.

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عنوان ژورنال:
  • Comput. Geom.

دوره 57  شماره 

صفحات  -

تاریخ انتشار 2016