Abstract
We prove that the (τ-weighted, sheaf-theoretic) SL(2, C) Casson–Lin invariant introduced by Manolescu and the first author is generically independent of the parameter τ and additive under connected sums of knots in integral homology 3-spheres. This addresses two questions asked by Manolescu and the first author. Our arguments involve a mix of topology and algebraic geometry, and rely crucially on the fact that the SL(2, C) Casson–Lin invariant admits an alternative interpretation via the theory of Behrend functions.
Original language | English |
---|---|
Journal | Journal of the Mathematical Society of Japan |
Volume | 74 |
Issue number | 3 |
Pages (from-to) | 683-717 |
ISSN | 0025-5645 |
DOIs | |
Publication status | Published - Jul 2022 |
Keywords
- sheaf-theoretic Floer homology, Casson–Lin invariants