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arXiv · 2007.08495

Rational pullbacks of toric foliations

Javier Gargiulo Acea·Ariel Molinuevo·Sebastián Velazquez
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Abstract

This article is dedicated to the study of singular codimension $1$ foliations $\mathcal{F}$ on a simplicial complete toric variety $X$ and their pullbacks by dominant rational maps $\varphi:\mathbb{P}^n\dashrightarrow X$. First, we describe the singularities of $\mathcal{F}$ and $\varphi^*\mathcal{F}$ for a generic pair $(\varphi,\mathcal{F})$. Then we show that the first order deformations of $\varphi^*\mathcal{F}$ arising from first order unfoldings are the families of the form $\varphi_\varepsilon^*\mathcal{F}$, where $\varphi_\varepsilon$ is a perturbation of $\varphi$. We also prove that the deformations of the form $\varphi^*\mathcal{F}_\varepsilon$ consist exactly of the families which are tangent to the fibers of $\varphi$. In order to do so, we state some results of independent interest regarding the Kupka singularities of these foliations.

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Javier Gargiulo Acea, Ariel Molinuevo, Sebastián Velazquez. 2020-07-16. Rational pullbacks of toric foliations. https://arxiv.org/abs/2007.08495

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