ZASSENHAUS CONJECTURE AND INFINITE NILPOTENT GROUPS

Zassenhaus conjectured that any torsion unit in an integral group ring ZG of a finite group G is rationally conjugate to +/-g for some g is an element of G. This has been confirmed for all finite nilpotent grou ps. We prove that such a result does not hold for infinite nilpotent g roups. (C) 1996 Academic Press, Inc.