2 problems

Let $L$ be a link in $S^3$, and let its fiber surface be the page of a fibration of its complement over $S^1$. A Hopf plumbing or deplumbing is the operation of adding or removing…

Let $M$ and $N$ be closed, connected, orientable $3$-manifolds. The open book genus $\mathrm{obg}(M)$ is the minimum genus among Heegaard splittings of $M$ induced by open book dec…