4 problems

Let $Q_{p,l}$ be the set of quaternions under consideration, let $x,y\in Q_{p,l}$, and write $\langle x,y\rangle'$ for the commutator subgroup of the subgroup generated by $x$ and…

Let $Q_{p,l}$ be the set of quaternions under consideration, and let $x,y\in Q_{p,l}$. Write $\langle x,y\rangle$ for the subgroup they generate, $\langle x,y\rangle'$ for its comm…

A quaternionic Hadamard matrix (QHM) is a quaternionic matrix whose entries have unit norm and whose rows are mutually orthogonal. Two QHMs are equivalent under the equivalence ope…

Let $T$ be a tensor in … The generic tensor-rank conjecture. The generic rank of $T$ is $3$. The preceding discussion suggests this quaternionic analogue of the complex generic-ran…