%0 Journal Article
%T Spectral characterization of sums of commutators II
%A Kenneth J. Dykema
%A Nigel J. Kalton
%J Mathematics
%D 1997
%I arXiv
%X For countably generated ideals, $\Jc$, of $B(\Hil)$, geometric stability is necessary for the canonical spectral characterization of sums of $(\Jc,B(\Hil))$--commutators to hold. This answers a question raised by Dykema, Figiel, Weiss and Wodzicki. There are some ideals, $\Jc$, having quasi--nilpotent elements that are not sums of $(\Jc,B(\Hil))$--commutators. Also, every trace on every geometrically stable ideal is a spectral trace.
%U http://arxiv.org/abs/math/9709208v1