Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Symmetry Group of Tzitzeica Surfaces PDE   Using the symmetry group theory of second order PDEs, one finds the symmetry
group associated to Tzitzeica surfaces partial differential equation. One
studies the inverse problem and one shows that the Tzitzeica surfaces PDE is an
Euler-Lagrange equation. One determines the variational symmetry group of the
associated functional and one obtains the conservation laws of the Tzitzeica
surfaces PDE. All these results shows that the Tzitzeica surfaces theory is
strongly related to variational problems and hence it is a subject of global
differential geometry.

12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-bio
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph