{ "id": "2104.03211", "version": "v1", "published": "2021-04-07T16:01:03.000Z", "updated": "2021-04-07T16:01:03.000Z", "title": "On the ranks of the additive and the multiplicative groups of a brace", "authors": [ "Andrea Caranti", "Ilaria Del Corso" ], "categories": [ "math.GR" ], "abstract": "In \\cite[Theorem 2.5]{Bac16} Bachiller proved that if $(G, \\cdot, \\circ)$ is a brace of order the power of a prime $p$ and the rank of $(G,\\cdot)$ is smaller than $p-1$, then the order of any element is the same in the additive and multiplicative group. This means that in this case the isomorphism type of $(G,\\circ)$ determines the isomorphism type of $(G,\\cdot)$. In this paper we complement Bachiller's result in two directions. In Theorem 2.2 we prove that if $(G, \\cdot, \\circ)$ is a brace of order the power of a prime $p$, then $(G,\\cdot)$ has small rank (i.e. $< p-1$) if and only if $(G,\\circ)$ has small rank. We also provide examples of groups of rank $p-1$ in which elements of arbitrarily large order in the additive group become of prime order in the multiplicative group. When the rank is larger, orders may increase.", "revisions": [ { "version": "v1", "updated": "2021-04-07T16:01:03.000Z" } ], "analyses": { "subjects": [ "20D15", "20B35", "12F10", "16T05", "20E18" ], "keywords": [ "multiplicative group", "isomorphism type", "small rank", "complement bachillers result", "arbitrarily large order" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }