3-manifolds efficiently bound 4-manifolds
3-manifolds efficiently bound 4-manifolds
It has been known since 1954 that every 3-manifold bounds a 4-manifold. Thus, for instance, every 3-manifold has a surgery diagram. There are several proofs of this fact, but little attention has been paid to the complexity of the 4-manifold produced. Given a 3-manifold M3 of complexity n, we construct …