A projection $p \neq 0$ in a von Neumann Algebra $A$ is called minimal, if for every projection $0\neq q\in A$ with $q \leq p$ already $q=p$.
I want to prove the following theorem:
For a minimal projection $p \in A$ the space $pAp$ is a division algebra.
Indeed $\mathbb{C}p=pAp$ which is isomormpic to the complex numbers.