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We solve a fundamental question posed in Frohardts 1988 paper [Fro] on finite $2$-groups with Kantor familes, by showing that finite groups with a Kantor family $(mathcal{F},mathcal{F}^*)$ having distinct members $A, B in mathcal{F}$ such that $A^* cap B^*$ is a central subgroup of $H$ and the quotient $H/(A^* cap B^*)$ is abelian cannot exist if the center of $H$ has exponent $4$ and the members of $mathcal{F}$ are elementary abelian. In a similar way, we solve another old problem dating back to the 1970s by showing that finite skew translation quadrangles of even order $(t,t)$ are always translation generalized quadrangles.
Let $G$ be a simple algebraic group of type $G_2$ over an algebraically closed field of characteristic $2$. We give an example of a finite group $Gamma$ with Sylow $2$-subgroup $Gamma_2$ and an infinite family of pairwise non-conjugate homomorphisms
Let $G$ be a linear algebraic group over an algebraically closed field of characteristic $pgeq 0$. We show that if $H_1$ and $H_2$ are connected subgroups of $G$ such that $H_1$ and $H_2$ have a common maximal unipotent subgroup and $H_1/R_u(H_1)$ an
Let $F_n$ be a free group of finite rank $n geq 2$. We prove that if $H$ is a subgroup of $F_n$ with $textrm{rk}(H)=2$ and $R$ is a retract of $F_n$, then $H cap R$ is a retract of $H$. However, for every $m geq 3$ and every $1 leq k leq n-1$, there
M.Newman has asked if it is the case that whenever H and K are isomorphic subgroups of a finite solvable group G with H maximal, then K is also maximal. This question was considered in a paper of I.M. Isaacs and the second author, where (among other
Motivated by some alternatives to the classical logical model of boolean algebra, this paper deals with algebraic structures which extend skew lattices by locally invertible elements. Following the meme of the Ehresmann-Schein-Nambooripad theorem, we