Sums of commutators in pure C*-algebras

@article{Ng2014SumsOC,
  title={Sums of commutators in pure C*-algebras},
  author={Ping Wong Ng and Leonel Robert},
  journal={arXiv: Operator Algebras},
  year={2014}
}
In a pure C ∗ -algebra (i.e., one having suitable regularity proper- ties in its Cuntz semigroup), any element on which all bounded traces vanish is a sum of 7 commutators. 
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