Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: De Donder Form for Second Order Gravity   We show that the De Donder form for second order gravity, defined in terms of
Ostrogradski's version of the Legendre transformation applied to all
independent variables, is globally defined by its local coordinate
descriptions. It is a natural differential operator applied to the
diffeomorphism invariant Lagrangian of the theory.

4
The categories of this paper are: cond-mat
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The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
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The categories of this paper are: physics
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th