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arXiv · 2306.15388

On reachability categories, persistence, and commuting algebras of quivers

Luigi Caputi·Henri Riihimäki
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Abstract

For a finite quiver $Q$, we study the reachability category $\mathbf{Reach}_Q$. We investigate the properties of $\mathbf{Reach}_Q$ from both a categorical and a topological viewpoint. In particular, we compare $\mathbf{Reach}_Q$ with $\mathbf{Path}_Q$, the category freely generated by $Q$. As a first application, we study the category algebra of $\mathbf{Reach}_Q$, which is isomorphic to the commuting algebra of $Q$. As a consequence, we recover, in a categorical framework, previous results obtained by Green and Schroll; we show that the commuting algebra of $Q$ is Morita equivalent to the incidence algebra of a poset, the reachability poset. We further show that commuting algebras are Morita equivalent if and only if the reachability posets are isomorphic. As a second application, we define persistent Hochschild homology of quivers via reachability categories.

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Luigi Caputi, Henri Riihimäki. 2023-06-27. On reachability categories, persistence, and commuting algebras of quivers. https://arxiv.org/abs/2306.15388

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