Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on "Bell's Theorem without Inequalities and without
  Probabilities for Two Observers"   In this Comment we show that Cabello's argument [Phys. Rev. Lett. 86, 1911
(2001)] which proves the nonlocal feature of any classical model of quantum
mechanics based on Einstein-Podolsky-Rosen (EPR) criterion of elements of
reality, must involve at least four distant observers rather than the two
employed by the author. Moreover we raise a remark on the necessity of
performing a real experiment confirming Cabello's argument.

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The categories of this paper are: q-bio
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
1
The categories of this paper are: cs
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The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
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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: hep-ex