2 problems

Let $d\in\mathbb{N}$, let $\mathcal{A}$ be a unital C-algebra, and let $\mathbb{MM}_{d\times d}(\mathcal{A})$ denote the $d\times d$ Manin matrices over $\mathcal{A}$. Let…

Bourgain–Tzafriri conjecture. There is a universal constant $A>0$ such that, for every $B>1$, there is a natural number $r=r(B)$ with the following property: for every natural numb…