Abstract
We define notions of a weak homotopy for finite hypergraphs and an exponential hypergraph with a right adjoint to the categorical product of finite hypergraphs, and investigate a connection between the weak homotopy and the exponential hypergraph. Then we discuss a Hom construction associated to a pair of finite hypergraphs and prove that the homotopy of hypergraph homomorphisms, defined in (Grigor’Yan et al. in Topol Appl 267:106877, 2019), could be characterized by properties of the Hom construction. In addition, we establish some properties of Hom constructions involving the categorical product of finite hypergraphs. As an application we show that the homotopy of d-colorings of a simple hypergraph \({\mathcal {H}}\) could be characterized by properties of Hom constructions associated to the maximum simple hypergraph and \({\mathcal {H}}\).
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This research was supported by the National Natural Science Foundations of China (No. 11771116) and the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (No. 2022L266).
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Zhang, C., Wang, Y., Zhang, Z. et al. Homotopy and Hom Construction in the Category of Finite Hypergraphs. Graphs and Combinatorics 39, 78 (2023). https://doi.org/10.1007/s00373-023-02672-6
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DOI: https://doi.org/10.1007/s00373-023-02672-6
Keywords
- Hom construction
- Homotopy of hypergraph
- Exponential hypergraph
- Hypergraph homomorphism
- Colorings of hypergraph
- Maximum simple hypergraph