Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Symmetry analysis of the 1+1 dimensional relativistic imperfect fluid
  dynamics   The flow of the relativistic imperfect fluid in two dimensions is discussed.
We calculate the symmetry group of the energy-momentum tensor conservation
equation in the ultrarelativistic limit. Group-invariant solutions for the
incompressible fluid are obtained

22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an