%0 Journal Article %T Homologies of path complexes and digraphs %A Alexander Grigor'yan %A Yong Lin %A Yuri Muranov %A Shing-Tung Yau %J Mathematics %D 2012 %I arXiv %X In this paper we introduce a path complex that can be regarded as a generalization of the notion of a simplicial complex. The main motivation for considering path complexes comes from directed graphs(digraphs). We obtain a new notion of the path homology and cohomology of a digraph. %U http://arxiv.org/abs/1207.2834v4