On Manolescu's $\kappa$-invariants of rational homology 3-spheres

Masaaki Ue

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arXiv · 2405.02597

On Manolescu's $\kappa$-invariants of rational homology 3-spheres

Masaaki Ue

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Abstract

We give an estimate for Manolescu's $\kappa$-invariant of a rational homology 3-sphere $Y$ by the data of a spin 4-orbifold bounded by $Y$. By an appropriate choice of a 4-orbifold, sometimes we can restrict and determine the value of $\kappa$. We give such examples in case of Dehn surgeries along knots in $S^3$.

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Masaaki Ue. 2024-05-04. On Manolescu's $\kappa$-invariants of rational homology 3-spheres. https://arxiv.org/abs/2405.02597

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