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arXiv · 2210.14787

Bracket width of the Lie algebra of vector fields on a smooth affine curve

Ievgen Makedonskyi·Andriy Regeta
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Abstract

We prove that the bracket width of the simple Lie algebra of vector fields $\rm{Vec}(C)$ of a smooth irreducible affine curve $C$ with a trivial tangent sheaf is at most three. In addition, if $C$ is a plane curve, the bracket width of $\rm{Vec}(C)$ is at most two and if moreover $C$ has a unique place at infinity, the bracket width of $\rm{Vec}(C)$ is exactly two. We also show that in case $C$ is rational, the width of $\rm{Vec}(C)$ equals one.

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Ievgen Makedonskyi, Andriy Regeta. 2022-10-26. Bracket width of the Lie algebra of vector fields on a smooth affine curve. https://arxiv.org/abs/2210.14787

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