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On the generalized Hadamard product and the Jordan-Hadamard product

Published online by Cambridge University Press:  17 April 2009

Jen-chung Chuan
Affiliation:
Department of Mathematics, National Tsing Hua University, Hsinchu, Taiwan 300, Republic of China.
Wai-fong Chuan
Affiliation:
Department of Mathematics, National Tsing Hua University, Hsinchu, Taiwan 300, Republic of China.
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Abstract

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The generalized Hadamard product S * T and the Jordan-Hadamard product S ∘ T of two operator-matrices S and T are introduced. They coincide with the usual Hadamard product of two complex matrices when the underlying Hilbert spaces are one-dimensional. Some inequalities which hold true for the usual Hadamard product of positive definite complex matrices are shown to be true for these two new products of positive invertible operator-matrices.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1980

References

[1]Ando, T., Topics on operator inequalities (Division of Applied Mathematics, Research Institute of Applied Electricity, Hokkaido University, Sapporo, 1978).Google Scholar
[2]Ando, T., “Concavity of certain maps on positive definite matrices and applications to Hadamard products”, Linear Algebra Appl. 26 (1979), 203241.CrossRefGoogle Scholar
[3]Arveson, William B., “Subalgebras of C*-algebras”, Acta Math. 123 (1969), 141224.CrossRefGoogle Scholar
[4]Hardy, G.H., Littlewood, J.E., Polya, G., Inequalities., 2nd edition (Cambridge University Press, Cambridge, 1959).Google Scholar
[5]Marcus, M. and Khan, N.A., “A note on the Hadamard product”, Canad. Math. Bull. 2 (1959), 8183.CrossRefGoogle Scholar
[6]Pusz, W. and Woronowicz, S.L., “Functional calculus for sesquilinear forms and the purification map”, Rep. Math. Phys. 8 (1975), 159170.CrossRefGoogle Scholar
[7]Stinespring, W. Forrest, “Positive functions on C*-algebras”, Proc. Amer. Math. Soc. 6 (1955), 211216.Google Scholar
[8]Styan, George P.H., “Hadamard products and multivariate statistical analysis”, Linear Algebra Appl. 6 (1973), 217240.CrossRefGoogle Scholar