Parametric connected sum
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Tex syntax errorand equipped with codimension 0-embeddings and of a compact connected manifold . It generalises the usual connected sum operation
which is the special case when is the -disc. The parametric connected sum operation is more complicated than the usual connectedsum operation since the isotopy classes of the embeddings of into
Tex syntax errormay be significantly more complicated than the isotopy classes of embeddings of n-discs need for connected sum: these last are determined by (local) orientations.
2 Connected sum along k-spheres
Tex syntax errorand it is sufficient to equip them with an isotopy class of embeddings of the k-disc. Moreover, the disjoint union is the unique thickening of . This motivates the following
Defintion 2.1.A manifold with an -thickening, an -thickened manifold for short, is a pair where
Tex syntax erroris a compact connected manifold and is an embedding.
Defintion 2.2. Let and by -thickened manifolds. Define
where is defined via the embeddings and .
It is clear that we have the following
Observation 2.3.The diffeomorphism type of depends only upon the the isotopy classes of the embeddings and (which of course includes the diffeomorphism types of
Tex syntax errorand ).
The analogue of such a construction for embeddings, the -parametric connected sum of embeddings, is used
- to define, for , a group stucture on the set of (smooth or PL) isotopy classes of embeddings [Skopenkov2006], \S3.4, [Skopenkov2006a], \S3, [Skopenkov2015a].
- to construct an action of this group on the set of isotopy classes of embeddings of certain -manifolds into [Skopenkov2014], 1.2.
- to estimate the set of isotopy classes of embeddings [Cencelj&Repovš&Skopenkov2007], [Cencelj&Repovš&Skopenkov2008], [Skopenkov2007], [Skopenkov2010], [Skopenkov2015], [Skopenkov2015a], [Crowley&Skopenkov2016] and unpublished paper [Crowley&Skopenkov2016a].
3 Parametric connected sum along thickenings
Let be a stable fibred vector bundle. A foundational theorem of modified surgery is
In particular, has the structure of an abelian group. The question of whether there is a geometric definition of this group structure is taken up in [Kreck1985, Chapter 2, pp 26-7] where it is shown how to use parametric connected sum along thickenings to define an addition of stable diffeomorphism classes of closed 2n-B-manifolds.
- [Ajala1984] S. O. Ajala, Differentiable structures on products of spheres, Houston J. Math. 10 (1984), no.1, 1–14. MR736571 (85c:57032) Zbl 0547.57026
- [Ajala1987] S. O. Ajala, Differentiable structures on a generalized product of spheres, Internat. J. Math. Math. Sci. 10 (1987), no.2, 217–226. MR886378 (88j:57028) Zbl 0627.57022
- [Cencelj&Repovš&Skopenkov2007] M. Cencelj, D. Repovš and M. Skopenkov, Homotopy type of the complement of an immersion and classification of embeddings of tori., Russ. Math. Surv.62 (2007), no.5, 985-987. Zbl 1141.57009
- [Cencelj&Repovš&Skopenkov2008] M. Cencelj, D. Repovš and M. Skopenkov, Classification of knotted tori in the 2-metastable dimension, Mat. Sbornik, 203:11 (2012), 1654-1681. Available at the arXiv:0811.2745.
- [Crowley&Skopenkov2016] D. Crowley and A. Skopenkov, Embeddings of non-simply-connected 4-manifolds in 7-space, I. Classification modulo knots, Moscow Math. J., 21 (2021), 43--98. arXiv:1611.04738.
- [Crowley&Skopenkov2016a] D. Crowley and A. Skopenkov, Embeddings of non-simply-connected 4-manifolds in 7-space, II. Smooth classification. Proc. A of the Royal Soc. of Edinburgh, to appear. arXiv:1612.04776
- [Kreck1985] M. Kreck, An extension of the results of Browder, Novikov and Wall about surgery on compact manifolds, preprint Mainz (1985).
- [Kreck1999] M. Kreck, Surgery and duality, Ann. of Math. (2) 149 (1999), no.3, 707–754. MR1709301 (2001a:57051) Zbl 0935.57039
- [Sako1981] Y. Sako, Connected sum along the cycle operation of on -manifolds, Proc. Japan Acad. Ser. A Math. Sci. 57 (1981), no.10, 499–502. MR640259 (83a:57043) Zbl 0505.57010
- [Skopenkov2006] A. Skopenkov, Embedding and knotting of manifolds in Euclidean spaces, in: Surveys in Contemporary Mathematics, Ed. N. Young and Y. Choi, London Math. Soc. Lect. Notes, 347 (2008) 248-342. Available at the arXiv:0604045.
- [Skopenkov2006a] A. Skopenkov, Classification of embeddings below the metastable dimension. Available at the arXiv:0607422.
- [Skopenkov2007] A. Skopenkov, A new invariant and parametric connected sum of embeddings, Fund. Math. 197 (2007), 253–269. arXiv:math/0509621. MR2365891 (2008k:57044) Zbl 1145.57019
- [Skopenkov2010] A. Skopenkov, Embeddings of k-connected n-manifolds into , Proc. AMS, 138 (2010) 3377--3389. Available at the arXiv:0812.0263.
- [Skopenkov2014] A. Skopenkov, How do autodiffeomorphisms act on embeddings, Proc. A of the Royal Society of Edinburgh, 148:4 (2018) 835--848.
- [Skopenkov2015] M. Skopenkov, When is the set of embeddings finite up to isotopy? Intern. J. Math. 26:7 (2015), http://arxiv.org/abs/1106.1878
- [Skopenkov2015a] A. Skopenkov, A classification of knotted tori, Proc. A of the Royal Society of Edinburgh, 150:2 (2020), 549-567. Full version: http://arxiv.org/abs/1502.04470