Finite sums of projections in purely infinite simple C*-algebras with torsion $K_0$
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- by Victor Kaftal, P. W. Ng and Shuang Zhang PDF
- Proc. Amer. Math. Soc. 140 (2012), 3219-3227 Request permission
Abstract:
Assume that $\mathscr {A}$ is a purely infinite simple C*-algebra whose $K_0$ is a torsion group, namely, contains no free element. Then a positive element $a\in \mathscr {A}$ can be written as a finite sum of projections in $\mathscr {A}$ if and only if either $a$ is a projection or $\|a\|>1$.References
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Additional Information
- Victor Kaftal
- Affiliation: Department of Mathematics, University of Cincinnati, P. O. Box 210025, Cincinnati, Ohio 45221-0025
- MR Author ID: 96695
- Email: kaftalv@ucmail.uc.edu
- P. W. Ng
- Affiliation: Department of Mathematics, University of Louisiana, 217 Maxim D. Doucet Hall, P.O. Box 41010, Lafayette, Louisiana 70504-1010
- MR Author ID: 699995
- Email: png@louisiana.edu
- Shuang Zhang
- Affiliation: Department of Mathematics, University of Cincinnati, P.O. Box 210025, Cincinnati, Ohio 45221-0025
- Email: zhangs@math.uc.edu
- Received by editor(s): December 9, 2010
- Received by editor(s) in revised form: March 28, 2011
- Published electronically: January 13, 2012
- Additional Notes: The third author was supported by a Taft Center Travel Grant when the article was presented in Beijing, China, in the summer of 2010.
- Communicated by: Marius Junge
- © Copyright 2012
American Mathematical Society
The copyright for this article reverts to public domain 28 years after publication. - Journal: Proc. Amer. Math. Soc. 140 (2012), 3219-3227
- MSC (2010): Primary 46L05; Secondary 47C15
- DOI: https://doi.org/10.1090/S0002-9939-2012-11152-9
- MathSciNet review: 2917094