Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solution to the mean king's problem using quantum error-correcting codes   We discuss the so-called mean king's problem, a retrodiction problem among
non-commutative observables, in the context of error detection. Describing the
king's measurement effectively by a single error operation, we give a solution
of the mean king's problem using quantum error-correcting codes. The existence
of a quantum error-correcting code from a solution is also presented.

25
The categories of this paper are: patt-sol
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: hep-th
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
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The categories of this paper are: eess
4
The categories of this paper are: cond-mat
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The categories of this paper are: q-bio
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The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc