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arXiv · 2512.08414

Weighted projective lines and Hochschild cohomology

Felix Schremmer
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Abstract

We describe the dimensions of Hochschild (co)homology groups of weighted projective curves over complex numbers. Surprisingly, all but one of those numbers depend only on the genus of the underlying non-weighted curve and the number of exceptional points. Our proof involves revising a classical representation-theoretic argument of Happel together with more recent results of Lenzing and Arinkin, C\u{a}ld\u{a}raru and Hablicsek. We give concrete realizations of a large class of weighted projective lines as quotient stacks. This paper conicides with the author's master's thesis submitted to the University of Bonn in 2019.

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Felix Schremmer. 2025-12-09. Weighted projective lines and Hochschild cohomology. https://arxiv.org/abs/2512.08414

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