Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Eight-Dimensional Topological Gravity and its Correspondence with
  Supergravity   A topological theory for euclidean gravity in eight dimensions is built by
enforcing octonionic self-duality conditions on the spin connection. The
eight-dimensional manifold must be of a special type, with G_2 or Spin(7)
holonomy. The resulting theory is related to a twisted version of N=1, D=8
supergravity. The situation is comparable to that of the topological
Yang--Mills theory in eight dimensions, for which the SO(8) invariance is
broken down to Spin(7), but is recovered after untwisting the topological
theory.

27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio