论文标题
在复杂双曲晶格三角形组中有限指数的亚组
On subgroups of finite index in complex hyperbolic lattice triangle groups
论文作者
论文摘要
我们在已知的复杂双曲线三角形组中研究了几个明确的有限指数亚组，并显示其中一些是整洁的，其中一些是阳性的betti数字，其中一些人在非亚洲自由组上具有同构。对于某些晶格三角组，我们确定整齐亚组的最小索引。最后，我们回答了一个由斯托弗（Stover）提出的问题，并用一个尖头描述了一个无限的整齐球标的塔。
We study several explicit finite index subgroups in the known complex hyperbolic lattice triangle groups, and show some of them are neat, some of them have positive first Betti number, some of them have a homomorphisms onto a non-Abelian free group. For some lattice triangle groups, we determine the minimal index of a neat subgroup. Finally, we answer a question raised by Stover and describe an infinite tower of neat ball quotients all with a single cusp.
