Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental Test of Leggett's Inequalities with Solid-State Spins   Bell's theorem states that no local hidden variable model is compatible with
quantum mechanics. Surprisingly, even if we release the locality constraint,
certain nonlocal hidden variable models, such as the one proposed by Leggett,
may still be at variance with the predictions of quantum physics. Here, we
report an experimental test of Leggett's nonlocal model with solid-state spins
in a diamond nitrogen-vacancy center. We entangle an electron spin with a
surrounding weakly coupled $^{13}C$ nuclear spin and observe that the entangled
states violate Leggett-type inequalities by more than four and seven standard
deviations for six and eight measurement settings, respectively. Our
experimental results are in full agreement with quantum predictions and violate
Leggett's nonlocal hidden variable inequality with a high level of confidence.

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The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th