Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Entropy of a quantum error correction code   We define and investigate a notion of entropy for quantum error correcting
codes. The entropy of a code for a given quantum channel has a number of
equivalent realisations, such as through the coefficients associated with the
Knill-Laflamme conditions and the entropy exchange computed with respect to any
initial state supported on the code. In general the entropy of a code can be
viewed as a measure of how close it is to the minimal entropy case, which is
given by unitarily correctable codes (including decoherence-free subspaces), or
the maximal entropy case, which from dynamical Choi matrix considerations
corresponds to non-degenerate codes. We consider several examples, including a
detailed analysis in the case of binary unitary channels, and we discuss an
extension of the entropy to operator quantum error correcting subsystem codes.

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The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
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The categories of this paper are: acc-phys
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
3
The categories of this paper are: physics
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The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci