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arXiv · 2506.23709

On outer automorphisms of certain graph $C^{*}$-algebras

Swarnendu Datta·Debashish Goswami·Soumalya Joardar
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Abstract

Given a countable abelian group $A$, we construct a row finite directed graph $\Gamma(A)$ such that the $K_{0}$-group of the graph $\textrm{C}^{\ast}$-algebra $\textrm{C}^{\ast}(\Gamma(A))$ is canonically isomorphic to $A$. Moreover, each element of $\textrm {Aut}(A)$ is a lift of an automorphism of the graph $\textrm{C}^{\ast}$-algebra $\textrm{C}^{\ast}(\Gamma(A))$.

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Swarnendu Datta, Debashish Goswami, Soumalya Joardar. 2025-06-30. On outer automorphisms of certain graph $C^{*}$-algebras. https://doi.org/10.1112/blms.70251

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