Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Entanglement in Classical Optics   The emerging field of entanglement or nonseparability in classical optics is
reviewed, and its similarities with and differences from quantum entanglement
clearly pointed out through a recapitulation of Hilbert spaces in general, the
special restrictions on Hilbert spaces imposed in quantum mechanics and the
role of Hilbert spaces in classical polarization optics. The production of
Bell-like states in classical polarization optics is discussed, and new
theorems are proved to discriminate between separable and nonseparable states
in classical wave optics where no discreteness is involved. The influence of
the Pancharatnam phase on a classical Bell-like state is deived. Finally, to
what extent classical polarization optics can be used to simulate quantum
information processing tasks is also discussed. This should be of great
practical importance because coherence and entanglement are robust in classical
optics but not in quantum systems.

35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
2
The categories of this paper are: math