Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on "Entanglement transformation between two-qubit mixed states
  by LOCC" [Phys. Lett. A 373 (2009) 3610]   The paper [Phys. Lett. A 373 (2009) 3610] by D.-C. Li analyzes the
transformation between two-qubit mixed states by local operations and classical
communication. We show that the proof of the main theorem, Theorem 2.6 in
[Phys. Lett. A 373 (2009) 3610] is not complete. Therefore the generalization
of Nielsen's theorem to mixed states still remains an open problem.

19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
14
The categories of this paper are: math-ph