Why rooting fails
arXiv:0708.1295
Abstract
I explore the origins of the unphysical predictions from rooted staggered fermion algorithms. Before rooting, the exact chiral symmetry of staggered fermions is a flavored symmetry among the four "tastes." The rooting procedure averages over tastes of different chiralities. This averaging forbids the appearance of the correct 't Hooft vertex for the target theory.
10 pages, 5 figures. Invited talk at the XXV International Symposium on Lattice Field Theory, July 30 - August 4 2007, Regensburg, Germany