Character varieties of knots and tropical curves

Series
Tropical Geometry Seminar
Time
Wednesday, September 8, 2010 - 10:00am for 1 hour (actually 50 minutes)
Location
Skiles 114
Speaker
Stavros Garoufalidis – Georgia Tech
Organizer
Josephine Yu
The moduli space of representations of a fundamental group of a knot in SL(2,C) is an affine algebraic variety, and generically a complex curve, with an explicit projection to C^2. The ideal that defines this curve has special type described by binomial and linear equations. I will motivate this curve using elementary hyperbolic geometry, and its Newton polygon in the plane using geometric topology. Finally, I will describe a heuristic method for computing the Newton polygon without computing the curve itself, using tropical implitization, work in progress with Josephine Yu. The talk will be concrete, with examples of concrete curves that come from knots. This talk involves classical mathematics. A sequel of it will discuss quantum character varieties of knots and tropical curves.