arXiv · 1504.00046
In a pure C*-algebra (i.e., one having suitable regularity properties in its Cuntz semigroup), any element on which all bounded traces vanish is a sum of 7 commutators.
Ping Wong Ng, Leonel Robert. 2015-03-31. Sums of commutators in pure C*-algebras. https://arxiv.org/abs/1504.00046
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