2 problems

Let $n\in\mathbb{N}$ with $n>1$, and let $\varphi:F\to M_n(G)$ be a ring embedding, where $G$ and $F$ are division rings. Suppose that $a$ and $b$ are positive integers satisfying…

Let $R$ be a commutative ring. A monomorphic Noetherian envelope is a Noetherian envelope whose canonical map from $R$ is injective. Nonexistence conjecture. There does not exist a…