Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Artificial light and quantum order in systems of screened dipoles   The origin of light is a unsolved mystery in nature. Recently, it was
suggested that light may originate from a new kind of order - quantum order. To
test this idea in experiments, we study systems of screened magnetic/electric
dipoles in 2D and 3D lattices. We show that our models contain an artificial
light -- a photon-like collective excitation. We discuss how to design
realistic devices that realize our models. We show that the ``speed of light''
and the ``fine structure constant'' of the artificial light can be tuned in our
models. The properties of artificial atoms (bound states of pairs of artificial
charges) are also discussed. The existence of artificial light (as well as
artificial electron) in condensed matter systems suggests that elementary
particles, such as light and electron, may not be elementary. They may be
collective excitations of quantum order in our vacuum. Our models further
suggest that a gauge theory is a string-net theory in disguise. Light is a
fluctuation of nets of large closed strings and charge is the end of open
strings.

6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an