Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Geometric and topological structures related to M-branes II: Twisted
  String and String^c structures   The actions, anomalies, and quantization conditions allow the M2-brane and
the M5-brane to support, in a natural way, structures beyond Spin on their
worldvolumes. The main examples are twisted String structures. This also
extends to twisted String^c structures, which we introduce and relate to
twisted String structures. The relation of the C-field to Chern-Simons theory
suggests the use of the String cobordism category to describe the M2-brane.

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The categories of this paper are: alg-geom
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
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The categories of this paper are: adap-org
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The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg