We obtain a representation of unitarily invariant norm in terms of Ky Fan norms [see R. Bhatia, Matrix Analysis, Springer, New York et al., 1997, p. 35]. Indeed we obtain a more general result in the context of Eaton triple with reduced triple. Examples are given.

Contact details are reproduced from the original publication and may be historical.

Piotr Niemiec

Jagiellonian University, Institute of Mathematics, ul. Łojasiewicza 6, 30-348 Kraków, Poland

piotr.niemiec@uj.edu.pl

Tin-Yau Tam

Dept. of Mathematics and Statistics, Auburn University, Auburn, AL 36849-5310, U.S.A.

tamtiny@auburn.edu
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P. Niemiec, T.-Y. Tam. “A Representation of G-invariant norms for Eaton Triple.” Journal of Convex Analysis 18 (2011), No. 1, 59–65. https://doi.org/10.68381/jca18003