A note on collapse, entropy, and vanishing of the Yamabe invariant of symplectic 4-manifolds
arXiv:1408.1586 · doi:10.1016/j.geomphys.2014.09.001
Abstract
We make use of -structures and technology developed by Paternain - Petean to compute minimal entropy, minimal volume, and Yamabe invariant of symplectic 4-manifolds, as well as to study their collapse with sectional curvature bounded from below. À la Gompf, we show that these invariants vanish on symplectic 4-manifolds that realize any given finitely presented group as their fundamental group. We extend to the symplectic realm a result of LeBrun which relates the Kodaira dimension with the Yamabe invariant of compact complex surfaces.
v2. added a reference and corrected a typo