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Fundamental groups of some special quadric arrangements

M. Amram·M. Teicher
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Abstract

In this work we obtain presentations of fundamental groups of the complements of three families of quadric arrangements in $\mathbb{P}^2$. The first arrangement is a union of $n$ quadrics, which are tangent to each other at two common points. The second arrangement is composed of $n$ quadrics which are tangent to each other at one common point. The third arrangement is composed of $n$ quadrics, $n-1$ of them are tangent to the $n$'th one and each one of the $n-1$ quadrics is transversal to the other $n-2$ ones.

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M. Amram, M. Teicher. 2007-05-29. Fundamental groups of some special quadric arrangements. https://arxiv.org/abs/math/0601454

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