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arXiv · 2004.11729

Positive operator-valued measures and densely-defined operator-valued frames

Benjamin Robinson·Bill Moran·Doug Cochran
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Abstract

In the signal-processing literature, a frame is a mechanism for performing analysis and reconstruction in a Hilbert space. By contrast, in quantum theory, a positive operator-valued measure (POVM) decomposes a Hilbert-space vector for the purpose of computing measurement probabilities. Frames and their most common generalizations can be seen to give rise to POVMs, but does every reasonable POVM arise from a type of frame? In this paper we answer this question using a Radon-Nikodym-type result.

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Benjamin Robinson, Bill Moran, Doug Cochran. 2020-04-24. Positive operator-valued measures and densely-defined operator-valued frames. https://arxiv.org/abs/2004.11729

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