Porod, U. Probab. Th. Rel. Fields (1995) 101: 277. doi:10.1007/BF01375829
We investigate theL2-speed of convergence to stationarity for a certain class of random walks on a compact connected Lie group. We give a lower bound on the number of stepsk necessary such that thek-fold convolution power of the original step distribution has anL2-density. Our method uses work by Heckman on the asymptotics of multiplicities along a ray of representations. Several examples are presented.