Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Entanglement and Discord of superposition of Greenberger-Horne-Zeilinger
  states   We calculate the analytic expression for geometric measure of entanglement
for arbitrary superposition of two $N$-qubit canonical orthonormal
Greenberger-Horne-Zeilinger ($GHZ$) states and the same for two $W$ states. In
course of characterizing all kinds of nonclassical correlations, explicit
formula for quantum discord (via relative entropy) for the former class of
states has been presented. Contrary to the $GHZ$ state, the closest separable
state to the $W$ state is not classical. Therefore, in this case the discord is
different from the relative entropy of entanglement. We conjecture that the
discord for the $N$-qubit $W$ state is $\log_2N$.

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The categories of this paper are: dg-ga
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
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The categories of this paper are: chem-ph
3
The categories of this paper are: physics
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The categories of this paper are: ao-sci
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The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
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The categories of this paper are: math-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: patt-sol