The Burau representation is not faithful for<i>n</i>= 5
The Burau representation is not faithful for<i>n</i>= 5
The Burau representation is a natural action of the braid group B_n on the free Z[t,t^{-1}]-module of rank n-1. It is a longstanding open problem to determine for which values of n this representation is faithful. It is known to be faithful for n=3. Moody has shown that it is …