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Norms and CB norms of Jordan elementary operators

Richard M. Timoney
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Abstract

We establish lower bounds for norms and CB-norms of elementary operators on B(H). Our main result concerns the operator Tx = axb + bxa and we show its norm is at least the product of the norms of a and b, proving a conjecture of M. Mathieu. We also establish some other results and formulae for the CB norm and norm of such T for special cases.

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Richard M. Timoney. 2003-08-07. Norms and CB norms of Jordan elementary operators. https://arxiv.org/abs/math/0308070

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