Stabilisation, Bordism and Embedded Spheres 4–manifolds
نویسنده
چکیده
It is one of the most interesting facts in 4–dimensional topology that even in simply–connected 4–manifolds, not every homology class of degree 2 can be represented by an embedded sphere. In 1978, M. Freedman and R. Kirby showed that many of the obstructions against constructing such a sphere vanish if one modifies the ambient 4–manifold by adding copies of products of 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 Spinc–bordism groups of Eilenberg–McLane spaces.
منابع مشابه
Stabilisation, Bordism and Embedded Spheres in 4–manifolds
It is one of the most important facts in 4–dimensional topology that there are 4–manifolds in which not every spherical homology class of degree 2 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...
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