Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electric-Magnetic Duality and Topological Insulators   We work out the action of the SL(2,Z) electric-magnetic duality group for an
insulator with a non-trivial permittivity, permeability and theta-angle. This
theory has recently been proposed to be the correct low-energy effective action
for topological insulators. As applications, we give manifestly SL(2,Z)
covariant expressions for the Faraday rotation at orthogonal incidence at the
interface of two such materials, as well as for the induced magnetic and
electric charges, slightly clarifying the meaning of expressions previously
derived in the literature. We also use electric-magnetic duality to find a
gravitational dual for a strongly coupled version of this theory using the
AdS/CFT correspondence.

8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin