Invertibility of linear combinations of two idempotents

Authors:
Hongke Du, Xiyan Yao and Chunyuan Deng

Journal:
Proc. Amer. Math. Soc. **134** (2006), 1451-1457

MSC (2000):
Primary 47A05, 47L07

DOI:
https://doi.org/10.1090/S0002-9939-05-08091-3

Published electronically:
October 18, 2005

MathSciNet review:
2199192

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Abstract | References | Similar Articles | Additional Information

Abstract: Let and be two idempotents on a Hilbert space. In this note, we prove that the invertibility of the linear combination is independent of the choice of , if and

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Additional Information

**Hongke Du**

Affiliation:
College of Mathematics and Information Science, Shaanxi Normal University, Xi’an 710062, People’s Republic of China

Email:
hkdu@snnu.edu.cn

**Xiyan Yao**

Affiliation:
College of Mathematics and Information Science, Shaanxi Normal University, Xi’an 710062, People’s Republic of China

Email:
yaoxiyan63@163.com

**Chunyuan Deng**

Affiliation:
College of Mathematics and Information Science, Shaanxi Normal University, Xi’an 710062, People’s Republic of China

Email:
cy-deng@263.net

DOI:
https://doi.org/10.1090/S0002-9939-05-08091-3

Keywords:
Idempotent,
invertibility,
linear combination of two idempotents

Received by editor(s):
June 19, 2004

Received by editor(s) in revised form:
December 20, 2004

Published electronically:
October 18, 2005

Additional Notes:
This research was partially supported by the National Natural Science Foundation of China (19771056)

Communicated by:
Joseph A. Ball

Article copyright:
© Copyright 2005
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication.