Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vortex and the Gradient of Divergence in Sobolev Spaces   The properties of the vortex and the gradient of divergence operators ( $
\text{rot}$ and $\nabla \text{div}$ ) are studied in the space $ \mathbf {L}_2
(G) $ in a bounded domain $ G \subset \textrm {R}^3 $ with a smooth boundary $
\Gamma$ and in the Sobolev spaces: $ \mathbf{C}(2k, m)(G)\equiv
\mathbf{A}^{2k}(G) \oplus \mathbf{W}^m(G)$. S.L. Sobolev studied boundary value
problems for the scalar polyharmonic equation $\Delta^m\,u=\rho$ in the spaces
$W_2^m(\Omega)$ with a generalized right-hand side and laid the foundation for
the theory of these spaces. Its constructions have matrix analogs, here are
some of them. Analogues of the spaces ${W}_2^{(m)}(G)$ in the classes $
\mathcal {A} $ and $ \mathcal {B} $ are the space $\mathbf{A}^{2k}(G)$ and
$\mathbf{W}^m(G)$ of orders $ 2k> 0 $ and $ m> 0 $, and $ \mathbf {A}^{-2k} (G)
$ and their dual spaces $ \mathbf{W}^{- m}(G) $. Pairs of spaces form a net of
Sobolev spaces, its elements are classes $ \mathbf{C}(2k, m)(G)\equiv
\mathbf{A}^{2k}(G) \oplus \mathbf{W}^m(G)$; the class $ \mathbf{C}(2k,
2k)$coincides with the Sobolev space $\mathbf{H}^{2k}(G)$. They belong to
$\mathbf{L}_{2}(G)$, if $k\geq 0$ and $m\geq 0$. A wide field of problems has
opened up: studying the operators $(\mathrm{rot})^p$, $ (\nabla \,
\mathrm{div})^p$ for $ p = 1,2, ...,$ and others in the network Sobolev spaces.

28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph