Signature jumps and Alexander polynomials for links (Q2827387)

The paper contains a proof that the absolute value of the signature of a link is a lower bound for the number of zeros of the Alexander polynomial on the unit circle.NEWLINENEWLINEAn alternative proof appears in the appendix (joint with Feller) of \textit{L. Liechti}'s paper [Osaka J. Math. 53, No. 1, 251--266 (2016; Zbl 1347.57016)]. I refer to that review for more on the background and ramifications of this result. (In particular, it should be stressed that many special cases were known -- for example knots -- but none of their proofs elegantly generalizes.) The paper also discusses some examples from the second author's link database which illustrate various phenomena with signature jumps and Alexander polynomial zeros lying on the unit circle.