English

The $k$-cycle shuffling with repeated cards

Probability 2026-03-31 v1 Combinatorics Representation Theory

Abstract

We investigate the kk-cycle shuffle on repeated cards, namely on a deck consisting of ll identical copies of each of mm card types, with total size n=mln=ml. We establish asymptotic results for the total variation mixing of this shuffle, including cutoff and explicit limiting profiles. For fixed ll, we show that the walk exhibits cutoff at time nklogn\frac{n}{k}\log n with window of order nk\frac{n}{k}, and we identify the limiting profile in terms of the total variation distance between Poisson distributions arising from quotient fixed-point statistics. When ll\to\infty with sufficiently slow growth, more precisely when l=o(logn)l=o(\log n), we prove that the cutoff location shifts to nk(logn12logl)\frac{n}{k}\left(\log n-\frac 12\log l\right), again with window of order nk\frac{n}{k}, and that the limiting profile is asymptotically Gaussian, arising from a Poisson comparison after normal approximation. The proof is based on an approximation of the shuffling measure by an explicitly tractable auxiliary measure, generalizing the k=2k=2 case from Jain and Sawhney (arXiv:2410.23944). The representation-theoretic framework underlying the analysis of this auxiliary measure follows from the work of Hough (arXiv:1605.00911) and Nestoridi and Olesker-Taylor (arXiv:2005.13437)

Keywords

Cite

@article{arxiv.2603.27433,
  title  = {The $k$-cycle shuffling with repeated cards},
  author = {Jiahe Shen},
  journal= {arXiv preprint arXiv:2603.27433},
  year   = {2026}
}

Comments

19 pages. Comments welcome!

R2 v1 2026-07-01T11:42:32.379Z