The Rohlin invariant and Z/2-valued invariants of homology spheres

Ricard Riba

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arXiv · 2010.11766

The Rohlin invariant and Z/2-valued invariants of homology spheres

Ricard Riba

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Abstract

In this paper we prove that the Rohlin invariant is the unique invariant inducing a homomorphism on the Torelli group. Using this result we generalize the construction of invariants of homology $3$-spheres from families of trivial 2-cocycles on the Torelli group given by Pitsch to include invariants with values on an abelian group with $2$-torsion.

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Ricard Riba. 2020-10-22. The Rohlin invariant and Z/2-valued invariants of homology spheres. https://arxiv.org/abs/2010.11766

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