Spectral embedding through weak* limit of finite-dimensional approximations

Fabrice Nonez

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arXiv · 2605.30186

Spectral embedding through weak* limit of finite-dimensional approximations

Fabrice Nonez

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Abstract

The scope of this text is to study a process that induces another proof of the Spectral Embedding Theorem: that any densely defined symmetric operator can be extended by a multiplication operator through an embedding of the Hilbert space into an $L_2$ space. Furthermore, that process is meant to be used for specific operators, where natural spectral embeddings or equivalences may be found. That process has previously been considered in arXiv:2411.06281 and in arXiv:2511.18189, where it has been introduced through nonstandard techniques. Our contribution aims to be the reformulation of the theory through classical analysis arguments, without the use of nonstandard techniques nor ultraproducts.

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Fabrice Nonez. 2026-05-28. Spectral embedding through weak* limit of finite-dimensional approximations. https://arxiv.org/abs/2605.30186

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