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arXiv · 2107.07935

A note on the parallel sum

Frank Hansen
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Abstract

By using a variational principle we find a necessary and sufficient condition for an operator to majorise the parallel sum of two positive definite operators. This result is then used as a vehicle to create new operator inequalities involving the parallel sum.

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Frank Hansen. 2021-07-16. A note on the parallel sum. https://doi.org/10.1016/j.laa.2021.11.013

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