Abstract
It is shown that if A and B are positive operators on a separable complex Hilbert space, then
for every unitarily invariant norm. When specialized to the usual operator norm ||·|| and the Schatten p-norms ||·|| p , this inequality asserts that
and
These inequalities improve upon some earlier related inequalities. Other norm inequalities for sums of positive operators are also obtained.
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Kittaneh, F. Norm Inequalities for Sums of Positive Operators. II. Positivity 10, 251–260 (2006). https://doi.org/10.1007/s11117-005-0032-z
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DOI: https://doi.org/10.1007/s11117-005-0032-z