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Extremal cases of exactness constant and completely bounded projection constant

Hun Hee Lee
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Abstract

We investigate some extremal cases of exactness constant and completely bounded projection constant. More precisely, for an $n$-dimensional operator space $E$ we prove that $λ_{cb}(E) = \sqrt{n}$ if and only if $ex(E) = \sqrt{n}$, which is equivalent to $λ_{cb}(E) < \sqrt{n}$ if and only if $ex(E) < \sqrt{n}$.

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Hun Hee Lee. 2006-04-25. Extremal cases of exactness constant and completely bounded projection constant. https://arxiv.org/abs/math/0502335

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