Volume 7 (2024)
Greene, Joshua Evan; Liechti, Livio
On the signature of a positive braid
Annales Henri Lebesgue, Volume 7 (2024), pp. 823-839.

Metadata

DOI10.5802/ahl.212
Keywords Signature, positive braid, chessboard surface, Goeritz form

Abstract

We show that the signature of a positive braid link is bounded from below by one-quarter of its first Betti number. This equates to one-half of the optimal bound conjectured by Feller, who previously provided a bound of one-eighth.


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