An SL_2(R) CassonLin invariant
An SL_2(R) CassonLin invariant

Jacob Rasmussen, University of Cambridge and IAS
Zoom link:https://princeton.zoom.us/j/453512481?pwd=OHZ5TUJvK2trVVlUVmJLZkhIRHFDUT09
In the early 90's, X.S. Lin defined a Cassontype invariant of knots in S^3 by counting representations pi_1(S^3K)> SU(2) with fixed holonomy around the meridian. This invariant was subsequently shown to be equivalent to the LevineTristram signature of K. I'll describe a similar construction, using representations to SL_2(R) and discuss some applications and connections to other known invariants.
This is joint work with Nathan Dunfield.