Link Groups and Alexander Duality
نویسنده
چکیده
The A−B slice problem is a reformulation of the topological 4−dimensional surgery conjecture, in terms of smooth decompositions of the 4−ball. This paper applies the theory of link groups of 4−manifolds, recently developed by the author [9], to formulate a candidate for an obstruction in the A − B slice program. The strength of this invariant is illustrated by the theorem that it provides an obstruction for the family of model decompositions of D . The problem in the general case is expressed in terms of Alexander duality for link groups.
منابع مشابه
Link groups and the A - B slice problem
The A − B slice problem is a reformulation of the topological 4−dimensional surgery conjecture in terms of decompositions of the 4−ball and link homotopy. We show that link groups, a recently developed invariant of 4−manifolds, provide an obstruction for the class of model decompositions, introduced by M. Freedman and X.-S. Lin. This unifies and extends the previously known partial obstructions...
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