Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Background Fields in 2+1 Topological Gravity   The partition function of 2+1 Chern-Simons Witten topological gravity has an
attractive interpretation in terms of the unbroken and broken phases of
gravity. We make this physical interpretation manifest using the background
field method.

0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
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The categories of this paper are: astro-ph
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga