{ "id": "2310.09459", "version": "v1", "published": "2023-10-14T00:50:05.000Z", "updated": "2023-10-14T00:50:05.000Z", "title": "A new lower bound for the number of conjugacy classes", "authors": [ "Burcu Çınarcı", "Thomas Michael Keller" ], "categories": [ "math.GR" ], "abstract": "In 2003, H\\'{e}thelyi and K\\\"{u}lshammer proposed that if $G$ is a finite group and $p$ is a prime dividing the group order, then $k(G)\\geq 2\\sqrt{p-1}$, and they proved this conjecture for solvable $G$ and showed that it is sharp for those primes $p$ for which $\\sqrt{p-1}$ is an integer. This initiated a flurry of activity, leading to many generalizations and variations of the result; in particular, today the conjecture is known to be true for all finite groups. In this note, we put forward a natural new and stronger conjecture, which is sharp for all primes $p$, and we prove it for solvable groups, and when $p$ is large, also for $p$-solvable groups.", "revisions": [ { "version": "v1", "updated": "2023-10-14T00:50:05.000Z" } ], "analyses": { "keywords": [ "lower bound", "conjugacy classes", "finite group", "solvable groups", "stronger conjecture" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }