Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Real Formulations of Complex Gravity and a Complex Formulation of Real
  Gravity   Two gauge and diffeomorphism invariant theories on the Yang-Mills phase space
are studied. They are based on the Lie-algebras $so(1,3)$ and
$\widetilde{so(3)}$ -- the loop-algebra of $so(3)$. Although the theories are
manifestly real, they can both be reformulated to show that they describe
complex gravity and an infinite number of copies of complex gravity,
respectively. The connection to real gravity is given. For these theories, the
reality conditions in the conventional Ashtekar formulation are represented by
normal constraint-like terms.

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The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con