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arXiv · 1201.4837

Finite sums of projections in purely infinite simple C*-algebras with torsion K_0

V. Kaftal·P. N. Ng·S. Zhang
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Abstract

Assume that A is a purely infinite simple C*-algebra whose K_0 is a torsion group, namely, contains no free element. Then a positive element a in A can be written as a finite sum of projections in A if and only if either a is a projection or the norm ||a||>1.

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V. Kaftal, P. N. Ng, S. Zhang. 2012-01-23. Finite sums of projections in purely infinite simple C*-algebras with torsion K_0. https://arxiv.org/abs/1201.4837

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