Broken Lefschetz fibrations and smooth structures on 4-manifolds
arXiv:1205.5439
Abstract
The broken genera are orientation preserving diffeomorphism invariants of closed oriented 4-manifolds, defined via broken Lefschetz fibrations. We study the properties of the broken genera invariants, and calculate them for various 4-manifolds, while showing that the invariants are sensitive to exotic smooth structures.
21 pages, 5 figures