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arXiv · 2510.08701

Automorphisms of locally string algebras

Sarafina Ford
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Abstract

It is known that automorphisms of finite-dimensional bound quiver algebras decompose into inner automorphisms and automorphisms which permute the vertices. In this paper, we show that for string algebras, automorphisms permuting vertices further decompose into a graded automorphism and a composition of certain types of exponential automorphisms. Moreover, the same decomposition applies to automorphisms of locally string algebras, which are an analogue of string algebras wherein the finite-dimensional condition is omitted.

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Sarafina Ford. 2025-10-09. Automorphisms of locally string algebras. https://arxiv.org/abs/2510.08701

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