Trace methods in twisted group algebras, II
James Osterburg, Donald S. Passman · Proceedings of the American Mathematical Society · 2002
In this note, we continue our discussion of trace methods in twisted group algebras. Specifically, we obtain the twisted analog of Bass’ theorem on the traces of idempotents in ordinary group algebras. Indeed, we show that with suitable normalization, the characteristic 0 0 trace values of an idempotent are all contained in a cyclotomic field. The proof is a variant of the original argument combined with a reduction to finitely presented groups.