We characterize sandwiched singularities in terms of their link in two different settings. We first prove that such singularities are precisely the normal surface singularities having self-similar non-archimedean links. We describe this self-similarity both in terms of Berkovich analytic geometry and of the combinatorics of weighted dual graphs. We then show that a complex surface singularity is sandwiched if and only if its complex link can be embedded in a Kato surface in such a way that its complement remains connected.

中文翻译：

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夹层表面奇点与自相似性的联系

我们根据它们在两种不同设置中的链接来表征夹层奇点。我们首先证明这样的奇点正是具有自相似非阿基米德链接的法向表面奇点。我们用 Berkovich 解析几何和加权对偶图的组合来描述这种自相似性。然后，我们证明了复杂表面奇点被夹在中间，当且仅当它的复杂链接可以嵌入到 Kato 表面中，使其补充保持连接。