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Relative genus bounds in indefinite four-manifolds

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 نشر من قبل Lisa Piccirillo
 تاريخ النشر 2020
  مجال البحث
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Given a closed four-manifold $X$ with an indefinite intersection form, we consider smoothly embedded surfaces in $X setminus $int$(B^4)$, with boundary a knot $K subset S^3$. We give several methods to bound the genus of such surfaces in a fixed homology class. Our techniques include adjunction inequalities and the $10/8 + 4$ theorem. In particular, we present obstructions to a knot being H-slice (that is, bounding a null-homologous disk) in a four-manifold and show that the set of H-slice knots can detect exotic smooth structures on closed $4$-manifolds.



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