Abstract
It is one of the most important facts in 4–dimensional topology that not every spherical homology class of a 4–manifold can be represented by an embedded sphere. In 1978, M Freedman and R Kirby showed that in the simply connected case, many of the obstructions to constructing such a sphere vanish if one modifies the ambient 4–manifold by adding products of 2–spheres, a process which is usually called stabilisation. In this paper, we extend this result to non–simply connected 4–manifolds and show how it is related to the –bordism groups of Eilenberg–MacLane spaces.
Citation
Christian Bohr. "Stabilisation, bordism and embedded spheres in 4–manifolds." Algebr. Geom. Topol. 2 (1) 219 - 238, 2002. https://doi.org/10.2140/agt.2002.2.219
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