Orthigonal projections in a von Neumann algebra

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Let $M$ be a von Neumann algebra. $p$ is a projection in $M$, it is trivial that $1-p$ is orthogonal to $p$. Does there exist a largest projection $q\in M$ such that $qp=0$?

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Yes, it's $1-p$. If $q\geq 1-p$ and $qp=0$, then $$ 1-p=(1-p)q=q-pq=q. $$