No homotopy 4-sphere invariants using ECH = SWF
arXiv:1905.10938 · doi:10.2140/agt.2021.21.2543
Abstract
In relation to the 4-dimensional smooth Poincaré conjecture we construct a tentative invariant of homotopy 4-spheres using embedded contact homology (ECH) and Seiberg-Witten theory (SWF). But for good reason it is a constant value independent of the sphere, so this null-result demonstrates that one should not try to use the usual theories of ECH and SWF. On the other hand, a corollary is that there always exist pseudoholomorphic curves satisfying certain constraints in (punctured) 4-spheres.
19 pages, to appear in Algebr. Geom. Topol. with grammatical edits