A generalization of Ito's theorem to skew braces

Autor: Tsang, Cindy
Rok vydání: 2023
Předmět:
Zdroj: J. Algebra 642 (2024), 367-399
Druh dokumentu: Working Paper
DOI: 10.1016/j.jalgebra.2023.12.012
Popis: The famous theorem of It\^{o} in group theory states that if a group $G=HK$ is the product of two abelian subgroups $H$ and $K$, then $G$ is metabelian. We shall generalize this to the setting of a skew brace $(A,{\cdot\,},\circ)$. Our main result says that if $A = BC$ or $A = B\circ C$ is the product of two trivial sub-skew braces $B$ and $C$ which are both left and right ideals in the opposite skew brace of $A$, then $A$ is meta-trivial. One can recover It\^{o}'s Theorem by taking $A$ to be an almost trivial skew brace.
Comment: 35 pages; Proposition 2.4 and Corollary 2.6 were modified (there was a small mistake in the proof in version 1), and the hypothesis in Lemma 6.4 was slightly relaxed. Also fixed some typos
Databáze: arXiv