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Remarks on Naimark's duality

Wojciech Czaja
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Abstract

We present an extension of Naimark's duality principle which states that complete systems in a Hilbert space are projections of $ω$-linearly independent systems of elements of an ambient Hilbert space. This result is presented in the context of other known extensions of Naimark's theorem.

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Wojciech Czaja. 2004-10-15. Remarks on Naimark's duality. https://arxiv.org/abs/math/0410348

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