Registry · Definition
IV.D259
tau-effective
formalized
IV.D259 — Boundary character
A boundary character on L is a group homomorphism chi : pi_1(L) -> U(1) assigning a phase to each homotopy class of loops. Since pi_1(L, omega) = F_2 = (free group on two generators), the character variety is T^2, matching the fiber torus of the fibered product structure.