Computer Programs:

• KnotTwister, this program finds representations of fundamental groups and computes twisted Alexander polynomials. These are used to give lower bounds on the knot genus resp. the Thurston norm, and they are used to give fibration obstructions. Furthermore it now computes twisted Alexander polynomials of knots which are isotopy invariants. Some help can be found in the documentation (this version is from 5/11/06).