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arXiv · 1210.5285

Approximate Double Commutants and Distance Formulas

Don Hadwin·Junhao Shen
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Abstract

We extend work of the first author concering relative double commutants and approximate double commutants of unital subalgebras of unital C*-algebras, including metric versions involving distance estimates. We prove metric results for AH subalgebras of von Neumann algebras or AF subalgebras of primitive C*-algebras. We prove other general results, including some for nonselfadjoint commutative subalgebras, using C*-algebraic versions of the Stone-Weierstrass and Bishop-Stone-Weierstrass theorems.

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Don Hadwin, Junhao Shen. 2012-10-18. Approximate Double Commutants and Distance Formulas. https://arxiv.org/abs/1210.5285

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