We explore hybrid subgroups of certain non-arithmetic lattices in $${\text {PU}}(2,1)$$ . In particular, we show that all of Mostow’s lattices are virtually hybrids; moreover, we show that some of these non-arithmetic lattices are virtually hybrids of two non-commensurable arithmetic lattices in $${\text {PU}}(1,1)$$ .

中文翻译：

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$${\text {PU}}(2,1)$$PU(2,1) 中的非算术混合格

我们探索 $${\text {PU}}(2,1)$$ 中某些非算术格的混合子群。特别是，我们证明了所有 Mostow 的格子实际上都是混合的；此外，我们表明这些非算术格中的一些实际上是 $${\text {PU}}(1,1)$$ 中两个不可公度的算术格的混合体。