English

Quasirandom groups enjoy interleaved mixing

Combinatorics 2023-09-01 v2 Group Theory

Abstract

Let GG be a group such that any non-trivial representation has dimension at least dd. Let X=(X1,X2,,Xt)X=(X_{1},X_{2},\ldots,X_{t}) and Y=(Y1,Y2,,Yt)Y=(Y_{1},Y_{2},\ldots,Y_{t}) be distributions over GtG^{t}. Suppose that XX is independent from YY. We show that for any gGg\in G we have P[X1Y1X2Y2XtYt=g]1/GG2t1dt1EhGtX(h)2EhGtY(h)2.|\mathbb{P}[X_{1}Y_{1}X_{2}Y_{2}\cdots X_{t}Y_{t}=g]-1/|G||\le\frac{|G|^{2t-1}}{d^{t-1}}\sqrt{\mathbb{E}_{h\in G^{t}}X(h)^{2}}\sqrt{\mathbb{E}_{h\in G^{t}}Y(h)^{2}}. Our results generalize, improve, and simplify previous works.

Keywords

Cite

@article{arxiv.2206.10603,
  title  = {Quasirandom groups enjoy interleaved mixing},
  author = {Harm Derksen and Emanuele Viola},
  journal= {arXiv preprint arXiv:2206.10603},
  year   = {2023}
}
R2 v1 2026-06-24T11:58:57.750Z