Permutations with few inversions are locally uniform
Abstract
We prove that permutations with few inversions exhibit a local-global dichotomy in the following sense. Suppose is a permutation chosen uniformly at random from the set of all permutations of with exactly inversions. If are chosen uniformly at random from , then asymptotically almost surely. However, if and are chosen so that , and , then . Moreover, if , then the restriction of to a random -point interval is asymptotically uniformly distributed over . Thus, knowledge of the local structure of reveals nothing about its global form. We establish that is the threshold for local uniformity and the threshold for inversions, and determine the behaviour in the critical windows. As pointed out by a referee, there are flaws in the proofs that do not seem easily rectifiable (see comments on pages 9 and 15). So the results stated above have not been established.
Cite
@article{arxiv.1908.07277,
title = {Permutations with few inversions are locally uniform},
author = {David Bevan},
journal= {arXiv preprint arXiv:1908.07277},
year = {2022}
}
Comments
17 pages; there are flaws in the proofs, so the claimed results have not been established