Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Espace de Hilbert d'op\'erateurs et Interpolation complexe   Let $H$ be an infinite dimensional Hilbert space. We show that there exists a
subspace of $B(H)$ which is isometric to $\ell_2$ and completely isometric to
its antidual in the sense of the theory of operator spaces recently developed
by Blecher-Paulsen and Effros-Ruan. Moreover this space is unique up to a
complete isometry. We denote it by $OH$. This space has several remarkable
properties in particular with respect to the complex interpolation method.

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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: cond-mat
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The categories of this paper are: stat
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The categories of this paper are: nlin
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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ph
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The categories of this paper are: q-bio
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: eess