Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A queer reduction of degrees of freedom   The classical dynamics of antisymmetric second-rank tensor matter fields is
analyzed. The conformally invariant action for the tensor field leads to a
positive-definite hamiltonian on the class of the solutions that are bounded at
the time infinity (plane waves). Only the longitudinal waves contribute to the
energy and momentum. The helicity proves to be equal to zero.

23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ