On the character variety of periodic knots and links

Abstract

A link L of the 3-sphere S3 is said to be g-periodic (g≥2 an integer) if there exists an orientation preserving auto-homeomorphism h of S3 such that h(L)=L, h is of order g and the set of fixed points of h is a circle disjoint from L. A knot is called periodic with rational quotient if it is obtained as the preimage of one component of a 2-bridge link by a g-fold cyclic covering branched on the other component. In this paper the authors introduce a method to compute the excellent component of the character variety of periodic knots (note that for hyperbolic knots the excellent component of the character curve contains the complete hyperbolic structure). Among other examples, this method is applied to the seven hyperbolic periodic knots with rational quotient in Rolfsen's table and with bridge number greater than 2.