Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Effective Lagrangian of Three Dimensional Quantum Chromodynamics   We consider the low energy limit of three dimensional Quantum Chromodynamics
with an even number of flavors. We show that Parity is not spontaneously
broken, but the global (flavor) symmetry is spontaneously broken. The low
energy effective lagrangian is a nonlinear sigma model on the Grassmannian.
Some Chern--Simons terms are necessary in the lagrangian to realize the
discrete symmetries correctly. We consider also another parametrization of the
low energy sector which leads to a three dimensional analogue of the
Wess--Zumino--Witten--Novikov model. Since three dimensional QCD is believed to
be a model for quantum anti--ferromagnetism, our effective lagrangian can
describe their long wavelength excitations (spin waves).

36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics