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A unifying view toward polyhedral products through panel structures

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 نشر من قبل Li Yu
 تاريخ النشر 2021
  مجال البحث
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 تأليف Li Yu




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A panel structure on a topological space is just a locally finite family of closed subspaces. A space together with a panel structure is called a space with faces. In this paper, we define the notion of polyhedral product over a space with faces. This notion provides a unifying viewpoint on the constructions of polyhedral products and generalized moment-angle complexes in various settings. We compute the stable decomposition of these spaces and use it to study their cohomology ring structures by the partial diagonal maps. Besides, we can compute the equivariant cohomology ring of the moment-angle complex over a space with faces with respect to the canonical torus action. The calculation leads to a notion of topological face ring of a space with faces, which generalizes the classical notion of face ring of a simplicial complex. We will see that many known results in the study of polyhedral products and moment-angle complexes can be reinterpreted from our general theorems on the polyhedral product over a space with faces. Moreover, we can derive some new results via our approach in some settings.



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