Norms and CB norms of Jordan elementary operators
نویسندگان
چکیده
منابع مشابه
Norms and CB Norms of Jordan Elementary Operators
We establish lower bounds for norms and CB-norms of elementary operators on B(H). Our main result concerns the operator Ta,bx = axb + bxa and we show ‖Ta,b‖ ≥ ‖a‖‖b‖, proving a conjecture of M. Mathieu. We also establish some other results and formulae for ‖Ta,b‖cb and ‖Ta,b‖ for special cases. Our results are related to a problem of M. Mathieu [13, 14] asking whether ‖Ta,b‖ ≥ c‖a‖‖b‖ holds in ...
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ژورنال
عنوان ژورنال: Bulletin des Sciences Mathématiques
سال: 2003
ISSN: 0007-4497
DOI: 10.1016/s0007-4497(03)00046-0