-isomorphisms, Jordan isomorphisms, and numerical range preserving maps

Authors:
Hwa-Long Gau and Chi-Kwong Li

Journal:
Proc. Amer. Math. Soc. **135** (2007), 2907-2914

MSC (2000):
Primary 47A12, 47B15, 47B49, 15A60, 15A04, 15A18

Published electronically:
May 8, 2007

MathSciNet review:
2317968

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Abstract | References | Similar Articles | Additional Information

Abstract: Let or , where is the algebra of a bounded linear operator acting on the Hilbert space , and is the set of self-adjoint operators in . Denote the numerical range of by It is shown that a surjective map satisfies

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Additional Information

**Hwa-Long Gau**

Affiliation:
Department of Mathematics, National Central University, Chung-Li 32001, Taiwan

Email:
hlgau@math.ncu.edu.tw

**Chi-Kwong Li**

Affiliation:
Department of Mathematics, College of William and Mary, Williamsburg, Virginia 23185

Email:
ckli@math.wm.edu

DOI:
http://dx.doi.org/10.1090/S0002-9939-07-08807-7

Keywords:
Numerical range,
Jordan product.

Received by editor(s):
May 12, 2006

Received by editor(s) in revised form:
June 1, 2006

Published electronically:
May 8, 2007

Additional Notes:
The research of the first author was supported by the National Science Council of the Republic of China

The research of the second author was supported by a USA NSF grant and an HK RCG grant.

Communicated by:
Joseph A. Ball

Article copyright:
© Copyright 2007
American Mathematical Society