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arXiv · 2608.15203

An exotic finite pretriangulated category over any algebraically closed field

Javier Díaz Cabrera·Fernando Muro
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Abstract

We show that, over any algebraically closed field of any characteristic, the category of finite-dimensional projective modules over the preprojective algebra of generalized Dynkin type $\mathbb{L}_2$ has a pretriangulated category structure which is neither an algebraic nor a topological triangulated category structure.

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BibTeXRIS

Javier Díaz Cabrera, Fernando Muro. 2026-08-15. An exotic finite pretriangulated category over any algebraically closed field. https://arxiv.org/abs/2608.15203

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