Finite groupoids of configurations of lines in $\mathbb{P}^{3}_{\mathbb{C}}$

Jake Kettinger

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arXiv · 2511.05454

Finite groupoids of configurations of lines in $\mathbb{P}^{3}_{\mathbb{C}}$

Jake Kettinger

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Abstract

In this paper, we investigate groupoids coming from configurations of lines in three-dimensional space. Given a point and two skew lines in $\mathbb{P}^{3}_{K}$ over a field $K$, there exists a unique line containing the given point and meeting the two given lines. We use this construction to define a projection function from one line to another by using a skew line as an auxiliary. This way, we may create a groupoid whose objects are lines in a configuration, and whose morphisms are induced by these projection functions. We look at specific configurations for $K=\mathbb{C}$ that yield groupoids with finite automorphism groups.

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Jake Kettinger. 2025-11-07. Finite groupoids of configurations of lines in $\mathbb{P}^{3}_{\mathbb{C}}$. https://arxiv.org/abs/2511.05454

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