A nonstandard proof of the spectral theorem for unbounded self-adjoint operators

Isaac Goldbring

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arXiv · 2104.01949

A nonstandard proof of the spectral theorem for unbounded self-adjoint operators

Isaac Goldbring

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Abstract

We generalize Moore's nonstandard proof of the Spectral theorem for bounded self-adjoint operators to the case of unbounded operators. The key step is to use a definition of the nonstandard hull of an internally bounded self-adjoint operator due to Raab.

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Isaac Goldbring. 2021-04-05. A nonstandard proof of the spectral theorem for unbounded self-adjoint operators. https://arxiv.org/abs/2104.01949

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