Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Homodyne detection and optical parametric amplification: a classical
  approach applied to proposed "loophole-free" Bell tests   Recent proposed ``loophole-free'' Bell tests are discussed in the light of
classical models for the relevant features of optical parametric amplification
and homodyne detection. The Bell tests themselves are uncontroversial: there
are no obvious loopholes that might cause bias and hence, if the world does,
after all, obey local realism, no violation of a Bell inequality will be
observed. Interest centres around the question of whether or not the proposed
criterion for ``non-classical'' light is valid. If it is not, then the
experiments will fail in their initial concept, since both quantum theorists
and local realists will agree that we are seeing a purely classical effect. The
Bell test, though, is not the only criterion by which the quantum-mechanical
and local realist models can be judged. It is suggested that the
quantum-mechanical models given in the proposals will also fail in their
detailed predictions. If the experiments are extended by including a range of
parameter values and by analysing, in addition to the proposed digitised
voltage differences, the raw voltages, the models can be compared in their
overall performance and plausibility.

18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol