Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlocality of cluster states of qubits   We investigate cluster states of qubits with respect to their non-local
properties. We demonstrate that a Greenberger-Horne-Zeilinger (GHZ) argument
holds for any cluster state: more precisely, it holds for any partial, thence
mixed, state of a small number of connected qubits (five, in the case of
one-dimensional lattices). In addition, we derive a new Bell inequality that is
maximally violated by the 4-qubit cluster state and is not violated by the
4-qubit GHZ state.

34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc