Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum MacWilliams Identities   We derive a relationship between two different notions of fidelity
(entanglement fidelity and average fidelity) for a completely depolarizing
quantum channel. This relationship gives rise to a quantum analog of the
MacWilliams identities in classical coding theory. These identities relate the
weight enumerator of a code to the one of its dual and, with linear programming
techniques, provided a powerful tool to investigate the possible existence of
codes. The same techniques can be adapted to the quantum case. We give examples
of their power.

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The categories of this paper are: atom-ph
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The categories of this paper are: math
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: physics
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat
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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: econ
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The categories of this paper are: patt-sol