Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Projection method and new formulation of leading-order anisotropic
  hydrodynamics   The introduced earlier projection method for boost-invariant and
cylindrically symmetric systems is used to introduce a new formulation of
anisotropic hydrodynamics that allows for three substantially different values
of pressure acting locally in three different directions. Our considerations
are based on the Boltzmann kinetic equation with the collision term treated in
the relaxation time approximation and the momentum anisotropy is included
explicitly in the leading term of the distribution function. A novel feature of
our work is the complete analysis of the second moment of the Boltzmann
equation, in addition to the zeroth and first moments that have been analyzed
in earlier studies. We define the final equations of anisotropic hydrodynamics
in the leading order as a subset of the analyzed moment equations (and their
linear combinations) which agree with the Israel-Stewart theory in the case of
small pressure anisotropies.

6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci