Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bidual as a weak nonstandard hull   We construct the weak nonstandard hull of a normed linear space X from *X
(the nonstandard extension of X) using the weak topology on X. The bidual (i.e.
the second dual) X" is shown to be isometrically isomorphic to the weak
nonstandard hull of X. Examples and applications to C*-algebras are given,
including a simple proof of the Sherman-Takeda Theorem. As a consequence, the
weak nonstandard hull of a C*-algebra is always a von Neumann algebra. Moreover
a natural representation of the Arens product is given.

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The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
3
The categories of this paper are: physics
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: nlin