中文

直积中子群序列的梯度

群论 2017-05-15 v2

摘要

对于有限生成群直积 G=A×BG = A \times B 的有限指数子群序列 {Un}n=1\{U_n\}_{n = 1}^\infty,我们证明一旦当 nn \to \infty[A:AUn],[B:BUn][A : A \cap U_n], [B : B \cap U_n] \to \infty,则有 limnmin{X:X=Un}[G:Un]=0\lim_{n \to \infty} \frac{\min\{|X| : \langle X \rangle = U_n\}}{[G : U_n]} = 0。我们的证明依赖于有限单群分类。对于有限表现的 A,BA,B,我们证明 limnlogTorsion(Unab)[G:Un]=0. \lim_{n \to \infty} \frac{\log |\mathrm{Torsion}(U_n^{\mathrm{ab}})|}{[G : U_n]} = 0.

关键词

引用

@article{arxiv.1609.08900,
  title  = {Gradients of sequences of subgroups in a direct product},
  author = {Nikolay Nikolov and Zvi Shemtov and Mark Shusterman},
  journal= {arXiv preprint arXiv:1609.08900},
  year   = {2017}
}