arXiv:1303.2354math.GT
Pin(2)-equivariant Seiberg-Witten Floer homology and the Triangulation Conjecture
Abstract
We define Pin(2)-equivariant Seiberg-Witten Floer homology for rational homology 3-spheres equipped with a spin structure. The analogue of Froyshov's correction term in this setting is an integer-valued invariant of homology cobordism whose mod 2 reduction is the Rokhlin invariant. As an application, we show that there are no homology 3-spheres Y of Rokhlin invariant one such that Y # Y bounds an acyclic smooth 4-manifold. By previous work of Galewski-Stern and Matumoto, this implies the existence of non-triangulable high-dimensional manifolds.
Seems odd that they did not provide a counter example. My suspicion there is an incorrect assumption for non fractal structures. PS: This is really one of those cases where a paper does not mean much. You really need to dig through http://arxiv.org/abs/1303.2354 and find the…
RetricView on HNParent context
Here is the actual paper: http://arxiv.org/pdf/1303.2354v4.pdf. It looks like this is their family of counter examples: A specific non-orientable five-dimensional manifold M5 with Sq1 ∆(M) ̸= 0 is constructed in [25]. Hence M5 is non-triangulable. To get non-orientable examples…
panicView on HNParent context