Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bundle gerbes for topological insulators   Bundle gerbes are simple examples of higher geometric structures that show
their utility in dealing with topological subtleties of physical theories. I
review a recent construction of torsion topological invariants for condensed
matter systems via equivariant bundle gerbes. The construction covers static
and periodically driven systems with time reversal invariance in 2 and 3 space
dimensions. It involves refinements of geometry of gerbes that are discussed in
the first lecture, the second one being devoted to the applications to
topological insulators.

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The categories of this paper are: patt-sol
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
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The categories of this paper are: funct-an
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The categories of this paper are: eess
9
The categories of this paper are: nlin
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: q-alg